Division 
Range 
Shelf  ..... 
Received 


1872 


UNIVERSITY  OF  CALIFORNIA 


GIFT  OF 


WILLIAM  OILMAN  THOMPSON. 


OXYHYDROGEN    BLOW-PIPE. 


FOURTEEN   WEEKS 


COURSE  IN  CHEMISTRY. 


J.  DORMAN  STEELE,  A.M., 

PRINCIPAL    OF    ELMIRA    FREE    ACADEMY. 


"Bright  and  glorious  is  that  revelation 
Written  all  over  this  great  world  of  ours." 

LONGFELLOW. 


NEW  YORK : 
PUBLISHED  BY  A.  S.  BARNES  &  CO., 

Ill  &'l!3  WILLIAM   STREET. 

1867. 


f  D  30 


Entered  according  to  act  of  Congress,  in  the  year  1867, 
BY  A.  S.  BARNES  &  CO., 

In  the  Clerk's  Office  of  the  District  Court  of  the  United  States  for  the 
Southern  District  of  New  York. 


LITTLE,  RENNIE  &  Co.,  GEORGE  W.  WOOD, 

STEBEOTYPEBS,  PBINTEB, 

430  BBOOXE  STBEET,  N.  T.  2  DUTCH  STBEET,  N.  T. 


PREFACE. 


IN  the  preparation  of  this  little  volume  the  author 
lays  no  claim  to  originality :  his  has  been  the  far 
humbler  task  of  endeavoring  to  express,  in  simple, 
interesting  language,  a  few  of  the  principles  and 
practical  applications  of  Chemistry.  There  is  a  large 
class  of  pupils  in  our  schools  who  can  pursue  this 
branch  only  a  single  term,  the  time  assigned  to  it  in 
most  institutions.  They  do  not  intend  to  become 
chemists,  nor  even  professional  students.  If  they 
wander  through  a  large  text-book,  they  become  con- 
fused by  the  multiplicity  of  strange  terms,  which 
they  cannot  tarry  to  master,  and,  as  the  result,  too 
often  only  "  see  men  as  trees  walking."  Attempts 
have  been  made  to  reach  this  class  by  omitting  or  dis- 
guising the  nomenclature  ;  but  this  robs  the  science 
of  its  mathematical  beauty  and  discipline,  while  it 
does  not  fit  the  student  to  read  other  chemical  works 
or  to  understand  their  formulae.  The  author  has 
tried  to  meet  this  wani  by  omitting  thafc  which  is 
perfectly  obvious  to  the  eye — that  which  everybody 
already  knows — that  which  could  not  be  long  re- 
tained in  the  memory — and  that  which  is  essential 


6  PREFACE. 

only  to  the  chemist.  He  has  not  attempted  to  make 
a  reference-book,  lest  the  untrained  mind  of  the 
learner  should  become  clogged  and  wearied  with  a 
multitude  of  detail.  He  has  sought  to  make  a  pleas- 
ant study  which  the  pupil  can  master  in  a  single 
term,  so  that  all  its  truths  may  become  to  him 
"household  words."  Botany,  Natural  Philosophy, 
and  Physiology  are  omitted,  since  they  are  now  pur- 
sued as  separate  branches.  Unusual  importance  is 
given  to  that  practical  part  of  chemical  knowledge 
which  concerns  our  every-day  life,  in  the  hope  of 
bringing  the  school-room,  the  kitchen,  the  farm,  and 
the  shop  in  closer  relationship.  This  work  is  de- 
signed for  the  instruction  of  youth,  and  for  their  sake 
clearness  and  simplicity  have  been  preferred  to  rec- 
ondite accuracy.  If  to  some  young  man  or  woman 
this  becomes  the  opening  door  to  the  grander  temple 
of  Nature  beyond,  the  author  will  be  abundantly  re- 
paid for  all  his  toil. 


SUGGESTIONS   TO   TEACHERS. 


IT  is  recommended  that  in  the  use  of  this  book  the  topical 
method  of  recitation  should  be  adopted.  So  far  as  possible,  the 
order  of  the  subjects  is  uniform — viz.,  Source,  Preparation,  Pro- 
perties, Uses,  etc.  The  subject  of  each  paragraph  indicates  a 
question  which  should  draw  from  the  pupil  all  the  substance  of 
what  follows.  At  each  recitation  the  scholar  should  be  prepared 
to  explain  any  point  passed  over  during  the  term,  upon  its  title 
being  given  by  the  teacher.  Such  reviews  at  eveiy  recitation  are 
of  incalculable  value.  While  some  are  reciting,  let  others  write 
upon  certain  topics  at  the  blackboard,  and  let  the  class  criticise 
the  thought,  the  language,  the  spelling,  and  the  punctuation. 
Let  each  pupil  keep  a  lecture-book,  in  which  to  record  under 
each  general  head  of  the  text-book  all  the  experiments,  descrip- 
tions, and  general  information  given  by  the  teacher  in  class.  In 
order  to  accustom  the  scholar  to  the  nomenclature,  use  the 
symbols  constantly  from  the  beginning :  they  may  seem  dull  at 
first,  but  if  every  compound  be  thus  named,  a  familiarity  with 
chemical  language  will  be  induced  that  will  be  as  pleasing  as  it 
will  be  profitable.  If  time  will  admit,  hi  addition,  have  weekly 
essays  prepared  by  the  class,  combining  information  from  every 
attainable  source. 


ELEMENTARY  CHEMISTRY. 


INTRODUCTION. 

CHEMISTRY  treats  of  the  specific  properties  of  mat- 
ter and  the  composition  of  bodies.  Examples :  gold 
is  yellow ;  water  is  composed  of  two  gases,  hydrogen 
and  oxygen. 

ORGANIC  CHEMISTRY  deals  with  those  substances 
that  have  been  produced  by  life.  Examples  :  flesh, 
wood.  INORGANIC  CHEMISTRY  is  confined  to  those 
bodies  that  have  not  been  formed  by  life.  Examples : 
metals,  rocks. 

An  ELEMENT  is  a  kind  of  matter  which  has  never 
been  separated  into  anything  else.  Examples  :  sil- 
ver, iron.  There  are  about  65  in  all,  of  which  52  are 
metals,  and  13  metalloids  or  non-metallic  substances. 

CHEMICAL  AFFINITY  is  that  force  that  causes  the 
elements  of  matter  to  unite  and  form  new  com- 
pounds. It  acts  at  distances  so  slight  as  to  be  in- 
sensible, and  upon  the  most  dissimilar  substances : 
the  more  dissimilar  the  stronger  the  union.  Ex- 
ample :  a  little  chlorate  of  potassa  and  sulphur  mixed 
in  a  mortar  will  not  combine,  but  a  slight  pressure 
of  the  pestle  will  bring  them  within  the  range  of  at- 
^raction,  and  they  will  burn  with  a  loud  explosion. 


10  ELEMENTABY    CHEMISTKY. 

Nothing  in  the  nature  or  appearance  of  any  element 
indicates  its  chemical  affinity.  We  can  only  tell  by 
trial  with  what  it  will  combine.  This  attraction  is  not 
a  mere  freak  of  nature,  but  a  law  stamped  upon  mat- 
ter by  God  himself  for  wise  and  beneficent  purposes. 

COMPOUNDS  are  utterly  unlike  their  elements  in  all 
their  properties.  Examples :  yellow  sulphur  and 
white  quicksilver  form  red  vermilion ;  the  inert 
nitrogen  and  the  oxygen  of  the  air  constitute  a  cor- 
rosive acid — aquafortis ;  charcoal,  hydrogen,  and 
nitrogen  produce  the  deadly  prussic  acid ;  solid 
charcoal  and  sulphur  make  a  colorless  liquid ;  poi- 
sonous and  offensive  chlorine  combines  with  the 
brilliant  metal  sodium  to  form  common  salt. 

HEAT  and  LIGHT  favor  chemical  action,  and  fre- 
quently develop  an  affinity  where  it  seemed  to  be 
wanting.  The  former  especially,  by  its  expansive 
force,  tends  to  drive  the  elements  of  a  compound 
without  the  range  of  old  attractions  and  within  that 
of  new  ones.  Examples  :  gun-cotton,  when  lying  in 
the  air,  is  apparently  harmless,  but  a  spark  of  fire 
will  produce  a  brilliant  flash,  and  it  disappears  as  a 
gas  :  nitrate  of  silver  turns  black  in  the  sun,  by  the 
action  of  the  light. 

SOLUTION  also  aids  in  chemical  change,  as  it 
destroys  cohesion  and  leaves  the  atoms  free  to  unite. 
Example :  carbonate  of  soda  and  tartaric  acid 
mixed  in  a  glass  will  not  combine,  but  a  little  water 
added  will  produce  a  violent  effervescence. 

The  CHEMICAL  EQUIVALENT  of  an  element  is  the 


ELEMENTAKY    CHEMISTKY.  11 

proportion  by  weight  in  which  it  unites  with  other 
elements.  There  is  no  chance-work  in  nature.  No 
matter  under  what  circumstances  a  compound  is 
formed,  the  proportion  of  its  elements  is  the  same. 
Example  :  the  carbonic  acid  produced  amid  the  roar 
of  a  conflagration  or  the  explosion  of  a  volcano  is  iden- 
tical with  that  made  in  the  quiet  burning  of  a  match. 

The  ATOMIC  THEOKY,  which  lies  at  the  basis  of 
chemistry,  as  now  understood,  supposes — 

1st.  That  bodies  are  composed  of  individual  and 
unchangeable  atoms. 

2d.  That  the  chemical  equivalent  represents  the 
relative  weight  of  the  atoms  of  different  kinds. 

3d.  That  compounds  are  formed  by  the  union  of 
different  kinds  of  atoms  in  the  proportion  of  their 
equivalents,  or  multiples  of  their  equivalents. 

4th.  That  the  chemical  equivalent  of  a  compound 
is  equal  to  the  sum  of  the  chemical  equivalents  of 
its  elements. 

NOMENCLATURE. — The  elements  which  were  known 
anciently  have  retained  their  names.  Those  dis- 
covered more  recently  are  named  from  some  pecu- 
liarity. Examples  :  chlorine,  from  its  green  color  ; 
bromine,  from  its  bad  odor.  Of  late  the  uniform 
termination  um  has  been  adopted. 

SYMBOLS. — The  first  letter  of  the  English  name 
has  been  taken  as  the  symbol.  When  that  would 
produce  confusion,  the  Latin  name  has  been  substi- 
tuted, and  in  some  cases  the  second  letter  added. 
Examples  :  carbon  and  chlorine  both  commence  with 


12 


ELEMENTARY  CHEMISTRY. 


C ;  so  the  latter  takes  Cl  for  its  symbol.  Silver  and 
silicon  both  begin  with  Si,  hence  the  former  assumes 
Ag,  from  its  Latin  name,  Argentum.  If  more  than 
one  equivalent  of  an  element  is  used  in  forming  a 
compound,  this  is  shown  by  writing  the  number  be- 
low the  symbol.  Example  :  O2  indicates  two  equiv- 
alents of  O.  In  the  use  of  the  following  table,  the 
symbol  should  recall,  not  the  name  of  the  element 
alone,  but  the  relative  weight  of  its  atoms.  Ex- 
ample :  O  means  8  parts  of  oxygen  by  weight. 

TABLE  OF  ELEMENTS   AND  EQUIVALENTS. 


ELEMENTS. 

Symbol. 

Equiv- 
alent. 

ELEMENTS. 

Symbol. 

Equiv 
alent. 

Aluminum, 

Al. 

13.70 

Niobium    (Columbi- 

Antimony  (Stibium), 

Sb. 

129.00 

um). 

Nb. 

48.80 

Arsenicum, 
Barium, 

As. 
Ba. 

75.00    Nitrogen, 
68.50    Norium. 

N. 
No. 

14.00 

Bismuth, 

Bi. 

210.30 

Osmium, 

Os. 

99.40 

Boron, 

Bo. 

10.90 

Oxygen, 

O. 

8.00 

Bromine, 

Br. 

80.00 

Palladium, 

Pd. 

53.20 

Cadmium^ 

Caesium, 

Cd. 
Cs. 

56.00  1  Phosphorus, 
123.40  !  Platinum, 

P. 
Pt. 

31.00 
98.60 

Calcium, 
Carbon, 

Ca. 
C. 

20.00 
6.00 

Potassium  (Kalium), 
Rhodium, 

K. 
Ro. 

39.00 
53.20 

Cerium, 

Ce. 

46.00 

Rubidium, 

Rb. 

85.36 

Chlorine, 

Cl. 

35.50 

Ruthenium, 

Ru. 

52.11 

Chromium. 

Cr. 

26.30 

Selenium, 

Se. 

39.70 

Cobalt, 

Co. 

29.50  1  Silicon, 

Si. 

14.00 

Copper  (Cuprum) 
Didymittm, 

Cu. 
D. 

31.70 
48.00 

'Silver  (Argentum), 
Sodium  (Natrium), 

Ag. 

Na. 

108.00 
23.00 

Erbium, 

E. 

Strontium, 

Sr. 

43.80 

Fluorine, 

F. 

19.00 

Sulphur, 

S. 

16.00 

Glucinum, 

Gl. 

4.70 

Tantalum, 

Ta. 

68.80 

Gold  (Aurum), 

Au. 

196.44 

Tellurium, 

Te. 

64.50 

Hydrogen, 

H. 

1.00 

Terbium, 

Tb. 

Iodine, 

I. 

127.00 

Thallium, 

51. 

Iridium, 

Ir. 

98.60 

Thorinum, 

Th. 

59.50 

Iron  (Ferrum), 

Fe. 

28.00 

Tin  (Stannum), 

Sn. 

59.00 

Lanthanum, 

La. 

46.00 

Titanium, 

Ti. 

25.00 

Lead  (Plumbum), 

Pb. 

103.60 

Tungsten       (  W  o  1  - 

Lithium, 

L. 

7.00 

fram), 

W. 

92.00 

Magnesium, 

Mg. 

12.16 

Uranium, 

U. 

60.00 

Manganese, 

Mi. 

27.48 

Vanadium, 

V. 

68.50 

Mercury  (Hydrargy- 

Yttrium, 

y. 

rum), 

Hg. 

100.00 

Zinc, 

Zn. 

32.60 

Molybdenum, 

M? 

48.00 

Zirconium, 

Zr. 

22.40 

Nickel, 

Ni. 

29.501 

ELEMENTARY  CHEMISTBY.  13 

A  BINARY  COMPOUND  is  a  union  of  two  elements, 
and  in  reading  it  the  electro-negative  is  placed  first 
and  distinguished  by  the  termination  ide.  Ex- 
amples :  chlorine  and  sodium  form  chloride  of  sodi- 
um ;  iodine  forms  iodides.  In  the  case,  however,  of 
phosphorus,  carbon,  and  sulphur,  the  termination 
uret  is  generally  used.  Example  :  iron  and  sulphur 
form  sulphuret  of  iron.  In  writing  the  symbols  the 
electro-positive  element  is  placed  first.  An  OXYD  is 
a  compound  of  O  with  an  element.  One  equivalent 
of  O  is  called  the  protoxyd ;  two,  the  deutoxyd  or 
binoxyd ;  three  of  O  to  two  of  the  other  element, 
the  sesquioxyd.  Oxygen  being  negative  to  iron, 
when  united  they  form  an  oxyd  of  iron,  which  is, 
therefore,  written  FeO ;  the  deutoxyd  of  iron  is  FeO2 ; 
the  tritoxyd  of  iron  is  FeO3 ;  the  sesquioxyd,  Fe2Oa. 

Binary  compounds  are  divided  into  three  classes — 
ACIDS,  BASES,  and  NEUTRALS. 

An  ACID  is  generally  sour,  and  reddens  blue  lit- 
mus and  green  cabbage.  It  always  unites  with  bases 
to  form  salts,  which  is  the  real  test  of  an  acid. 
Acids  are  of  two  kinds — Oxacids  and  Hydracids  ; 
the  former  contain  O,  the  latter,  H.  The  oxacids 
are  named  from  the  element  with  which  the  O 
unites,  the  termination  indicating  their  strength — ic 
the  stronger  and  ous  the  weaker.  Example  :  sul- 
phur forms  two  acids  of  different  strength — sulphu- 
ric and  sulphurous.  If  an  acid  has  been  found 
containing  more  0  than  the  stronger,  it  takes  the 


14  ELEMENTABY  CHEMISTRY. 

prefix  per;  if  one  having  less  O,  the  prefix  hypo. 
Examples  • 

Chloric  acid C1O5. 

Chlorous  acid C1O3. 

Perchloric  acid C1O7. 

Hypochlorous  acid CIO. 

The  hydracids  combine  the  names  of  both  ele- 
ments. Examples :  hydrogen  and  chlorine  form 
hydrochloric  acid;  hydrogen  and  sulphur  make 
hydrosulphuric  acid. 

A  BASE  is  a  substance  that  unites  with  an  acid  to 
form  a  salt.  An  alkali  is  a  base  that,  in  addition, 
has  a  soapy  taste  and  feel,  and  changes  red  litmus 
to  blue,  and  red  cabbage  to  green.  It  turns  the  ium 
of  its  termination  to  a.  Example  :  NaO  is  called 
the  oxyd  of  sodium,  and  also  soda.  The  alkalies 
neutralize  the  acids,  and  each  restores  the  color  re- 
moved by  the  other. 

SALTS  are  ternary  compounds,  being  composed  of 
three  elements.  They  are  formed  by  the  union  of 
an  acid  and  a  base.  In  naming  a  salt  the  termina- 
tion of  the  acid  is  changed — an  ic  acid  forming  an 
ate  compound,  and  an  ous  acid  an  ite  compound.  The 
equivalent  of  O  combined  in  the  base  is  omitted. 
Examples :  NaO.SO3  is  read,  sulphate  of  soda ; 
FeO.SO3,  the  sulphate  of  iron,  and  not  the  sulphate 
of  the  protoxyd  of  iron  ;  CaO.SO2,  sulphite  of  lime. 

NEUTRALS  have  neither  the  properties  of  an  acid 


ELEMENTAKY   CHEMISTRY.  15 

nor  a  base.  Examples :  NaCl,  chloride  of  sodium ; 
KI,  iodide  of  potassium. 

FORMULA  is  an  algebraic  statement  of  the  symbols 
and  relations  of  several  compounds.  The  -f-  sign 
indicates  a  feeble  attraction  or  a  mere  mixture.  The 
=  sign  indicates  conversion  into.  The  period  de- 
notes a  combination.  The  brackets  and  coefficients 
are  used  as  in  algebra. 

The  following  list  of  symbols  are  given  for  prac- 
tice and  a  thorough  drill. 

PRINCIPAL  ACIDS. 

Sulphuric  Acid  (Oil  of  Vitriol) 80s 

Nitric  Acid  (Aquafortis) , NOs 

Chloric  Acid C1O5 

Phosphoric  Acid POs 

Carbonic  Acid CO2 

Sulphurous  Acid SO2 

Nitrous  Acid NO4 

Hydrochloric  Acid HC1 

THE  ALKALIES. 

P— otassa  (Potash) KO 

S— oda NaO 

A — mmonia NHs 

L— ime CaO 

M — agnesia MgO 

SALTS. 

Sulphate  of  Iron  (Green  Vitriol) .p FeO.SOa 

Sulphate  of  Copper  (Blue  Vitriol) CuO .  SOa 

Sulphate  of  Zinc  (White  Vitriol) ZnO.  SOa 


16  ELEMENTABY  CHEMISTRY. 

Sulphate  of  Potash KO.SOs 

Chlorate  of  Potash KO.ClOs 

Nitrate  of  Soda NaO .  NO5 

Nitrate  of  Potash  (Saltpetre) KO .  NO5 

Carbonate  of  Lime  (Limestone,  Chalk) CaO.CO2 

Carbonate  of  Soda  (Soda) NaO .  CO2 

Bicarbonate  of  Potash  (Saleratus) KO  .2CO2 

Sulphite  of  Soda NaO.SO2 

Sulphide  of  Iron FeS         % 

Sulphuret  of  Iron FeS 

Chloride  of  Sodium  (common  salt) NaCl 

Bhioxyd  of  Manganese MnO2 

Protoxyd  of  Hydrogen  (water) HO 

juioxyd  of  Iron  (iron-rust) Fe2  Os 


MATHEMATICS  OF  THE  LAW  OF  EQUIVALENTS. — The 
beauty  and  simplicity  of  the  Divine  law  of  harmony 
that  runs  like  a  silken  thread  through  all  nature, 
giving  unity  and  completeness  everywhere,  are  best 
seen  by  some  practical  applications.  It  is  evident, 
from  the  fourth  principle  of  the  atomic  theory,  that 
the  proportion  of  any  element  in  a  compound  is 
equal  to  its  equivalent  divided  by  the  equivalent  of 
the  compound.  Example:  HO— 1  +  8=9;  hence 
the  proportion  of  H  in  any  quantity  of  water  is  £, 
and  the  proportion  of  O  is  -f.  Again :  the  propor- 
tion of  that  element  or  constituent  in  a  given  weight 
of  the  compound  must  be  equal  to  the  weight  mul- 
tiplied by  this  fraction  we  have  just  named.  Ex- 
ample :  In  4  Ibs.  of  HO  there  are  4  x-J-  lb.  of  H=$ 
lb.,  and  4xf  lb.  of  O=-3/=3f  Ibs.  For  conveni- 


ELEMENTARY   CHEMISTRY.  17 

ence  we  can  put  this  thought  into  the  following  al- 
gebraic form,  under  which  should  be  solved  the  ex- 
amples which  follow,  and  many  other  similar  ones, 
which  the  ingenuity  of  teacher  and  scholar  will  sug- 
gest. The  book  should  be  searched  for  symbols  of 
compounds,  and  this  part  referred  to  throughout  the 
study. 

. .     (  Equivalent  of  the  constituent 
Weight  of  one  constituent=weight  of  given  quantity  -J  •=?— .- 

\  Equivalent  of  the  compound 

1.  In  making  O  from  chlorate  of  potash  (KO. 
C1O5),  how  much  can  be  obtained  from  two  pounds 
of  the  salt? 

2.  In  making  H  zinc  is  used.     How  much  sulphate 
of  zinc  (ZnO.SO3  +  7HO)  will  be  formed  from  2  Ibs. 
of  the  metal? 

3.  How  much  S03  will  be  required  to  make  50  Ibs. 
sulphate  of  iron  (FeO.SO3  +  7HO)  ? 

4.  The  equivalent  of  the  chloride  of  sodium  (salt) 
is  58.5.     In  10  Ibs.  there  are  6yf  T  Ibs.  of  sodium ; 
what  is  the  equivalent  of  Cl  ? 

5.  In  20  grains  of  bromide  of  potassium  there 
are   G^V   grains   of   potassium ;   the  equivalent  of 
potassium  being  39,  what  is  the  equivalent  of  the 
bromide  of  potassium? 

6.  In  14  Ibs.  of  iron-rust  (Fe2O3)  how  much  O  ? 

7.  In  20  Ibs.  of  glass  (NaO.SiO2  +  CaO.SiO2)  how 
many  Ibs.  of  sand  (SiG2)  ? 

8.  In  a  25  Ib.  sack  of  salt  (NaCl)  how  many  Ibs. 
of  the  metal  sodium  ? 


INORGANIC  CHEMISTRY. 


THE  METALLOIDS. 

OXYGEN. 

Symbol,  O  ••••  Equivalent,  8  ••••  Specific  Gravity,  I.I. 
THE  name  O  means  acid-former,  and  was  given 
because  it  was  supposed  to  be  the  essential  princi- 
ple of  all  acids ;  but  hydrogen  has  since  been  found 
to  possess  the  same  property. . 

Source. — O  is  the  most  abundant  of  all  the  ele- 
ments— comprising  |  of  the  air,  -f  of  the  water,  J  of 
all  animal  bodies,  and  \  of  the  crust  of  the  earth. 
Preparation. — The  simplest  method  of  making  O 

for  experimental 
purposes  is  to 
heat  a  mixture  of 
chlorate  of  pot- 
ash and  black 
oxyd  of  manga- 
nese in  a  retort, 
and  collect  the 
gas  over  a  pneu- 
matic cistern,  as 
in  the  accompany- 
ing  illustration. 


.  OXYGEN.  19 

The  reaction —the   chemical   change — is    as    fol- 
lows: 

KO.C1O6 


KC1    6O 

The  Cl  of  the  chloric  acid  unites  with  the  K  of 
the  potash,  forming  KC1,  chloride  of  potassium  ;  and 
the  5  atoms  of  O  in  the  chloric  acid  and  the  atom  of 
O  in  the  potash,  making  6  atoms  of  O,  pass  off  as  a 


A  Curious  Fact. — If  the  chlorate  of  potash  were 
heated  alone,  when  the  requisite  temperature  was 
reached  the  gas  would  be  liberated  with  very  great 
rapidity.  Sometimes,  indeed,  the  change  would  be 
instantaneous — the  solid  of  scarcely  a  cubic  inch 
becoming  in  the  twinkling  of  an  eye  a  gas  of  300 
cubic  inches,  and,  with  an  explosion  like  gunpowder, 
rending  the  retort  into  a  thousand  fragments.  If, 
however,  we  mix  with  the  chlorate  of  potash  a  little 
black  oxyd  of  manganese,  the  gas  will  come  off 
quietly  and  safely,  a  bubble  at  a  time.  At  the  con- 
clusion of  the  process,  the  MnO2  (the  binoxyd,  or 
black  oxyd  of  manganese)  will  be  found  unchanged. 
The  reason  of  this  wonderful  action  is  beyond  our 
comprehension.  It  would  seem  that  powdered 
glass  or  sand  should  produce  the  same  result ;  but, 
on  trial,  they  fail.  This  influence  of  one  body 
over  another,  by  its  mere  presence,  is  called  ca- 
talysis. 


20 


ELEMENTARY   CHEMISTRY. 


Properties. — O  has  no  odor,  color,  or  taste.  It 
combines  with  every  element  except  fluorine.  From 
some  of  its  compounds  it  can  be  set  free  by  the 
stroke  of  a  hammer,  while  from  others  it  can  be 
liberated  only  by  the  most  powerful  means.  Its 
union  with  a  substance  is  called  oxydation,  and  the 
product  an  oxyd.  It  is  a  most  powerful  supporter 
of  combustion. 

Example:  By  blowing  quickly  upward  upon  a 
candle  extinguish  the  flame, 
and  leave  a  glowing  wick. 
If  this  be  plunged  into  a 
jar  of  pure  O,  it  will  burst 
into  a  brilliant  blaze.  The 
experiment  may  be  repeated 
many  times  before  the  gas  is 
candle  in  oxygen.  exhausted.  Carbonic  acid  is 

formed  by  the  combustion. 

Example  :  If  a  watch-spring  be  straightened  in  a 
spirit-lamp,  and  then  tipped 
with  melted  sulphur,  on  ig- 
niting this  and  lowering  it 
into  a  jar  of  O,  the  steel  will 
crackle  into  a  shower  of  fiery 
stars,  and  melted  globules 
of  oxyd  of  iron  will  fly  in 
watch-spring  in  oxygen.  every  direction. 


OXYGEN. 


21 


Example  :  Ignite  a  bit  of  sulphur  placed  on  a 
stand,  and  invert  over  it  a  jar 
of  O  :  it  will  burn  with  a  beau- 
tiful blue  light,  and  the  fumes 
of  sulphurous  acid  (SO2)  will 
circle  about  the  receiver  in  cu- 
rious concentric  rings. 

Sulphur  in  oxygen. 

Example  :  Place  in  the  bottom  of  a  "  deflagrating 
spoon"  a  little  fine, 
dry  chalk  ;  then  wipe 
a  bit  of  phosphorus 
very    carefully    and 
quickly     between 
pieces    of    blotting- 
paper  ;  lay  this  upon 
the  chalk,  and,  hold- 
ing the  spoon  over 
a  large  jar  of  O,  ig- 
nite the  phosphorus 
with  a  heated  wire, 
and  lower  it  steadily 
into  the  gas.     The  phosphorus  will  burst  into   a 
blinding  flood  of  light,  while  dense  fumes  of  phos 
phoric  acid  (PO6)  will  roll  down  the  sides  of  the 
jar. 

THE  DESTKUCTIVE  AGENT  OF  THE  Am.  —  0  is  the  ac- 
tive principle  of  the  atmosphere.  It  is  destructive  in 
all  its  effects.  Comprising  one-fifth  of  common  air,  it 


Phogphoru8  in  oxygen.  »The  phosphoric 


22  ELEMENTAKY  CHEMISTRY. 

is  all  around  us,  and,  like  a  lurking  lion,  constantly 
on  the  watch  for  a  chance  to  spring  upon  and  devour 
something.  "We  gather  a  basket  of  luscious  peaches, 
and  put  them  out  of  the  way  of  the  children ;  but 
we  cannot  outreach  the  slyest  pilferer  of  all — the 
O — and  soon  we  will  find  the  fruit  covered  with  the 
prints  of  invisible  teeth.  Black  spots  appear,  and 
we  say  they  are  decaying ;  it  is  only  the  O  feasting 
upon  them,  and  in  a  month  it  will  devour  them, 
skin  and  all.  To  prevent  this,  we  put  our  fruit  in  a 
glass  can,  heat  it  to  expel  the  O,  seal  it  up  tightly, 
and  then  it  is  safe  from  this  chemical  plunderer. 

"We  open  the  damper  of  the  stove,  and  the  air 
rushes  in.  The  O  immediately  attacks  the  fuel. 
Each  pair  of  atoms  catches  up  an  atom  of  C  between 
them,  and  flies  off  into  the  air  as  carbonic  acid. — An 
animal  dies.  The  O  is  on  the  alert ;  and,  the  in- 
stant his  victim  expires,  and  sometimes  a  little 
sooner,  he  is  so  anxious  to  commence,  he  begins  to 
remove  that  which  will  soon  be  an  offence  to  all  sen- 
sitive nostrils. — We  accidentally  cut  a  finger,  and 
soon  find  the  unwelcome  O  tugging  away  at  the 
quivering  nerve  beneath. —  The  keen  throb  with 
which  an  unsuspected  hollow  in  a  tooth  is  revealed 
to  us,  announces  the  entrance  of  the  foe  at  an  un- 
guarded breach. — The  HO  in  the  cistern  becomes 
foul  and  putrid.  We  uncover  it.  In  rushes  the  O, 
picks  up  every  atom  of  impurity,  and  drags  it  to  the 
bottom.  The  thick  sediment  we  find  when  we  clean 
it  t  e  next  summer,  shows  how  faithfully  it  did  its 


OXYGEN.  23 

work.* — We  use  our  writing-fluid,  and  the  words 
look  pale  and  dejected.  In  a  few  hours  we  return, 
and  even  the  letters  stand  out  bold  and  clear. 
Noiselessly  uniting  with  the  iron  of  the  ink,  the 
skilful  intruder  has  not  disturbed  the  most  delicate 
tracery  in  taking  possession. — The  blacksmith  draws 
a  red-hot  iron  from  his  forge.  The  O  seizes  the  op- 
portunity while  the  metal  is  glowing,  and  bites  off 
great  scales  of  the  black  oxyd  of  iron  (Fe3  O4)  that 
fly  in  every  direction. — We  wipe  our  knives  and 
forks,  and  carefully  lay  them  away ;  but  if  we  have 
left  on  them  the  least  particle  of  moisture,  as  HO 
favors  chemical  change,  the  vigilant  O  will  find  it, 
and,  if  unmolested,  will  never  stop  until  it  has  eaten 
the  whole  of  the  feast  we  have  provided.  But  as 
heat  is  also  productive  of  chemical  action,  and  the 
Fe  is  now  cold,  it  cannot  combine  as  vigorously  as 
at  the  blacksmith's  forge ;  therefore,  the  compound 
is  a  lower  one,  the  red  oxyd  of  iron  (Fe2O3)  or  com- 
mon iron-rust,  as  we  see  it  on  stoves  and  other 
utensils. 

O  IN  THE  HUMAN  SYSTEM. — We  take  the  air  into 
our  lungs.  Every  three  minutes  all  the  blood  in  the 
system  makes  the  tour  of  the  body,  and  comes  to 

*  "  As  the  vessel  sets  sail  from  London,  the  captain  fills  the 
water-casks  with  water  from  the  river  Thames,  foul  with  the  sewage 
of  the  city,  and  containing  23  different  species  of  animalcules ; 
yet,  in  a  few  days,  the  O  contained  in  the  air  dissolved  by  the 
HO,  will  have  cleansed  it,  and  the  HO  will  be  found  sweet  and 
wholesome  during  the  voyage." 


24  ELEMENTARY  CHEMISTRY. 

the  lungs.  Now  the  blood  is  full  of  little  iron  disks, 
or  gas-bags.  These,  when  old,  assume  a  tawny  hue, 
like  the  decayed  leaves  of  autumn,  shrivel  up  and 
die,  millions  of  them  perishing  at  every  breath  we 
draw.  But  when  young  and  vigorous,  they  take  up 
the  O  and  cany  it  to  all  parts  of  the  body,  deposit- 
ing it  wherever  it  is  needed.  Here  the  O  revels  in 
high  life.  It  sweeps  tingling  through  every  artery 
and  vein,  distends  each  capillary  tube,  sends  the 
quick  flush  to  the  cheek,  snatches  up  its  portion 
of  the  food  that  comes  out  of  the  stomach,  gnaws 
away  at  the  nerves  and  tissues,  eats  up  every  worn- 
out  muscle  and  all  waste  matter,  until  at  last  it  comes 
back  through  the  veins  black  and  thick  with  the  pro- 
ducts of  its  toil — the  cinders  of  the  fire  within  us. 

COMBUSTION  AND  HEAT. — All  processes  of  fermen- 
tation, of  decay,  of  putrefaction,  of  fire,  are  called, 
by  the  chemist,  by  one  name — combustion,  or  oxyd- 
ation.  They  are  simply  produced  by  the  union  of 
O  with  the  substance.  They  differ  only  in  the  time 
employed  in  the  operation.  If  O  unites  rapidly,  we 
call  it  fire ;  if  slowly,  decay.  Yet  the  process  and 
the  products  are  the  same.  A  stick  of  wood  is 
burned  in  my  stove,  and  another  rots  in  the  woods, 
and  the  chemical  change  is  identical.  In  the  com- 
bustion of  an  atom  of  O,  a  certain  amount  of  heat  is 
liberated.  Hence,  the  house  that  decays  in  twenty 
years,  gives  out  as  much  heat  during  that  time  as  if 
it  had  been  swept  off  in  a  fierce  conflagration  in  as 
many  minutes. 


OXYGEN.  25 

THE  HUMAN  FUBNACE. — The  body  is  a  stove  in 
which  fuel  is  burned,  and  the  chemical  action  is  pre- 
cisely like  that  in  any  other  stove.  This  combustion 
liberates  heat,  and  our  bodies  are  kept  warm  by  the 
constant  fire  within  us.  We  thus  see  why  we  fortify 
ourselves  against  a  cold  day  by  an  extra  full  meal. 
When  there  is  plenty  of  fuel  in  our  human  furnaces, 
the  O  burns  that ;  but  if  there  be  a  deficiency,  the 
destructive  O  must  still  unite  with  something,  so  it 
gnaws  away  at  our  flesh ; — first  the  fat,  and  the  man 
grows  poor ;  then  the  muscles,  and  he  grows  weak ; 
finally  the  brain,  and  he  becomes  crazed.  He  has 
simply  burned  up,  as  a  candle  burns  out  to  dark- 
ness. 

O  PEODUCES  MOTION. — The  action  of  O  in  the 
movement  of  the  muscles  is  very  singular.  In  order 
to  move  a  limb,  the  muscle  must  contract.  So  the 
O  unites  with  a  part  of  the  muscle,  destroys  its 
structure,  and  so  shortens  it.  Thus  every  movement 
of  a  limb,  every  wink  of  the  eye,  even,  is  performed 
by  the  disintegration  of  the  muscle  used.  The 
truth  of  this  is  shown  very  clearly  when  we  remem- 
ber that,  as  soon  as  we  begin  to  perform  any  unusual 
exercise,  we  commence  breathing  more  rapidly, — 
showing  that  we  need  more  O  to  unite  with  the 
muscles  to  perform  the  work.  In  very  violent  labor, 
as  in  running,  we  are  compelled  to  open  our  mouths, 
and  take  in  great  swallows  of  oxygen.  This  roaring 
fire  within  elevates  the  temperature  of  the  body,  and 
we  say  "  we  are  so  warm  that  we  pant."  Really  it  is 


26  ELEMENTAEY  CHEMISTEY. 

the  reverse.  The  panting  is  the  cause  of  our  wamth. 
We  need  O,  then,  not  only  to  keep  us  warm,  but  also 
to  do  all  our  work.  Cut  off  its  supply,  and  we  grow 
cold,  the  heart  struggles  spasmodically  for  an  in- 
stant, but  the  motive  power  is  gone,  and  the  wheels 
of  life  soon  stand  still.* 

THE  BURNING  OF  THE  BODY  BY  O. — A  man  weighing 
150  Ib.  has  64  Ib.  of  muscle.  This  would  be  burned 
in  about  80  days  of  ordinary  labor.  As  the  heart 
works  day  and  night,  it  burns  out  in  about  a  month. 
So  that  we  have  a  literal  "  new  heart"  every  thirty 
days.  We  thus  dissolve,  melt  away  in  time,  and 
only  the  shadow  of  our  bodies  can  be  called  our 
own.  They  are  like  the  flame  of  a  lamp,  which  ap- 
pears for  a  long  time  the  same,  since  it  is  "  cease- 
lessly fed  as  it  ceaselessly  melts  away."  The  rapidity 
of  this  change  in  our  bodies  is  remarkable.  Says 
Dr.  Draper :  "  Let  a  man  abstain  from  water  and 


*  During  sleep,  the  organs  of  the  body  are  mostly  at  rest,  ex- 
cept the  heart.  To  produce  this  small  muscular  exertion  very 
little  O  is  required.  As  our  respiration  is,  therefore,  slight,  our 
pulse  sinks,  the  heat  of  our  body  falls,  and  we  need  much  addi- 
tional clothing  to  keep  warm.  Animals  that  hibernate  show  the 
same  truth.  The  marmot,  for  instance,  in  summer  is  warm- 
blooded; hi  the  winter  its  pulse  sinks  from  140  to  4,  and  it  becomes 
cold-blooded.  The  bear  goes  to  his  cave  in  the  fall,  fat  and 
plump ;  in  the  spring  he  conies  out  lean  and  lank.  Cold-blooded 
animals  have  very  inferior  breathing  apparatus.  A  snake,  for 
example,  has  to  swallow  air  by  mouthfuls,  as  we  do  water.  Others 
have  no  lungs  at  all,  and  breathe  hi  a  little  air  through  their  skin, 
enough  to  barely  exist.  Is  it  strange  they  are  cold-blooded  ? 


OXYGEN.  27 

food  an  hour,  and  the  balance  will  prove  he  has  be- 
come lighter."  At  night  a  person  is  not  quite  so 
tall  as  in  the  morning.  A  French  physiologist  says 
his  son  lost  an  inch  by  a  single  night's  dancing. 
This  action  of  O,  so  destructive — wasting  us  away 
constantly  from  birth  to  death — is  yet  essential  to 
our  existence.  Why  is  this  ?  Here  is  the  glorious 
paradox  of  life.  We  live  only  as  we  die.  The  moment 
we  cease  dying,  we  cease  living.  All  our  life  is  pro- 
duced by  the  destruction  of  our  bodies.  Hence  the 
necessity  for  food  to  supply  the  constant  waste  of 
our  system,  and  for  sleep  to  give  nature  time  to  re- 
pair the  losses  of  the  day.  Thus,  also,  we  see  why 
we  feel  exhausted  at  night  and  refreshed  in  the 
morning. 

O  THE  COMMON  SCAVENGER. — God  has  no  idlers  in 
his  world.  Each  atom  has  its  use.  There  is  not 
an  extra  particle  in  the  entire  universe.  So  the  O 
collects  every  waste  substance,  picks  up  every  strag- 
gler, and  returns  it  to  the  common  stock,  for  use  in 
nature's  laboratory.  In  performing  this  task,  its 
mission  is  most  important  and  necessary.  It  sweet- 
ens water,  it  keeps  the  avenues  of  the  body  open  and 
unclogged,  it  preserves  the  air  wholesome.  Oxygen 
is,  in  a  word,  the  universal  scavenger  of  nature.  No 
matter  can  hide  away  from  its  keen  eye.  Every 
dark  cellar  of  the  city,  every  recess  of  the  body,  every 
nook  and  cranny  of  creation,  finds  it  waiting ;  and 
the  instant  an  atom  is  exposed,  the  oxygen  pounces 
upon  it.  A  leaf  falls,  and  the  0  forthwith  commences 


28  ELEMENTARY  CHEMISTRY. 

its  destruction.  A  tiny  twig,  far  out  at  the  end  of  a 
limb,  dies,  and  the  O  immediately  begins  its  removal. 
A  pile  of  decaying  vegetables,  a  heap  of  rubbish, 
the  dead  body  of  an  animal,  a  fallen  tree,  even  the 
houses  we  erect  for  our  shelter  the  very  instant  they 
are  built,  all  are  gnawed  upon  by  what  we  call  the 
"  insatiate  tooth  of  time."  It  is  only  the  constant 
corrosion  of  this  destructive  agent — oxygen. 

ACTION  OF  PURE  O  IN  THE  BODY. — The  action  of 
undiluted  oxygen  on  the  animal  system  is  exhilarat- 
ing in  the  highest  degree.  A  rabbit  immersed  in  a 
receiver  of  this  gas  soon  feels  its  effect,  bounds  off 
into  a  delirium  of  excitement,  and  in  a  few  hours  by 
this  quick  combustion  burns  out  its  little  lamp  of 
life.  Were  we  to  breathe  pure  O,  the  fiery  gas  would 
leap  through  our  arteries  like  a  hungry  tiger,  the 
heart  would  throb  against  the  ribs  with  the  stroke 
of  a  trip-hammer,  the  veins  would  dilate  with  the 
increasing  tide  of  blood,  the  eyes  would  glisten  and 
glare :  the  gestures  and  motions  would  be  at  first 
quick,  lively,  vivacious,  then  hurried  and  restless, 
then  eager  and  startling,  at  last  furious  and  raving ; 
and  if  the  inhalation  of  the  gas  still  continued,  stark 
insanity  would  end  the  drama  of  life. 

KESULTS  IF  THE  AIR  WERE  PURE  O. — Were  the  air 
pure  O,  the  fire  element  would  run  riot  everywhere. 
Our  lamps  would  burn  with  the  oil  they  contain. 
Our  stoves  would  blaze  with  a  shower  of  sparks.  A 
fire  once  kindled  would  spread  with  ungovernable 
velocity.  In  a  conflagration,  not  only  would  the 


OXYGEN. 


29 


timber  of  a  ho;ise  burn,  but  the  nails,  the  foundation, 
and  even  the  very  water  poured  upon  it  to  extinguish 
the  flames. 

OZONE. — Ozone  is  an  dttoircpic  form  of  O — i.  e.,  a 
form  in  which  the  element  itself  is  so  changed  as  to 
have  new  properties.  It  is  always  perceived  during 
the  working  of  an  electric  machine,  and  is  then 
called  "the  electric  smell."  It  has  also  been  de- 
tected near  objects  just  struck  by  lightning.  The 
electricity  of  the  atmosphere  is  supposed  to  have 
something  to  do  with  its  formation.  Its  test  is  a 
paper  wet  with  a  mixture  of  starch  and  iodide  of 
potassium  (KI).  The  ozone  sets  free  the  iodine,  and 
that  unites  with  the  starch,  forming  the  blue  iodide 
of  starch.  Its  identity  with  0  is  easily  shown.  Ex- 
ample :  Pour  a  little  ether 
into  a  jar  of  common  air, 
and  stir  in  its  vapor  a 
heated  glass  rod.  The 
O  will  be  immediately 
changed  into  its  allotrop- 
ic  form — ozone,  which  can 
be  recognized  by  its  pun- 
gent odor  and  the  test 
just  named.  If  the  ozone 
be  afterward  passed  Making  ozone, 

through  a  red-hot  tube,  it  will  come  out  the  original 
O.  Ozone  is  much  more  corrosive  even  than  oxygen. 
It  bleaches  powerfully,  and  is  a  rapid  disinfectant. 
A  piece  of  tainted  meat  plunged  into  a  jar  of  ozone 


30  ELEMENTARY  CHEMISTRY. 

is  instantly  purified.  Its  abundance  in  the  air  pro- 
duces influenzas,  diseases  of  the  lungs,  etc. ;  its  ab- 
sence, fevers,  agues,  etc. 


NITROGEN. 

Symbol,  N  ....  Equivalent,  14.... Specific  Gravity,  0,97. 

This  gas  is  called  nitrogen  because  it  exists  in 
nitre. 

Sources. — Nitrogen  is  found  largely  in  ammonia 
and  nitric  acid.  It  forms  \  of  dried  flesh,  f  of  the  at- 
mosphere, and  exists  abundantly  in  mushrooms, 
mustard,  cabbage,  horse-raddish,  turnips,  etc.  The 
peculiar  odor  of  burnt  hair  or  woollen  is  given  by 
the  N  compounds  they  contain. 

Preparation. — It  is  prepared  by  putting  in  the 
centre  of  a  deep  dish  of  water  a  little  stand  several 
inches  in  height,  on  which  a  bit  of  phosphorus  may 
be  laid  and  ignited.  As  the 
fumes  of  phosphoric  acid  ascend, 
invert  a  receiver  over  the  stand. 
The  phosphorus  will  consume  all 
of  the  O  of  the  air  contained  in 
the  jar,  leaving  the  N.  As  the 

Making  nitrogen.  water     ^     tlie     plate     riseg)     add 

more  as  needed.  It  should  occupy  ^  of  the  receiver. 
The  jar  will  at  first  be  filled  with  white  fumes  (PO5), 
but  the  water  in  a  few  minutes  will  absorb  these. 

Another  Method.  —  Nitrogen  may  also  be  pre- 
pared in  large  quantities  in  the  manner  shown  in  the 


NITROGEN. 


31 


illustration.  At  the  left  is  a  stream  of  water  which 
falls  through  a  funnel  tube  into  a  "  Woulfe's  bottle." 
The  U-shaped  tube  is  filled  with  bits  of  chloride  of 


Making  nitrogen. 

calcium  to  absorb  the  moisture ;  and  a  second  tube 
should  be  added,  filled  with  pumice-stone,  moistened 
with  caustic  potash,  to  deprive  the  air  of  its  carbonic 
acid.  The  long  tube  is  filled  with  copper  turnings, 
heated  by  the  furnace-fire.  The  air  from  the  bottle 
is  driven  by  the  f  ailing  water  up  through  the  U  tubes, 
where  it  loses  its  water  and  carbonic  acid;  thence 
among  the  red-hot  copper-turnings,  whicji  unite  with 
its  O  :  after  which  the  N,  deprived  of  all  its  com- 
panions, bubbles  up  through  the  water  into  the 
receiver. 


32  ELEMENTAKY  CHEMISTRY. 

Properties. — All  descriptions  of  nitrogen  are  of  a 
negative  character.  It  neither  burns  nor  permits 
anything  else  to  burn.  It  neither  supports  life  nor 
destroys  it.  Yet  a  candle  will  not  burn  in  it,  and  a 
person  cannot  breathe  it  alone  and  live,  simply  be- 
cause it  shuts  off  the  life-giving  oxygen.  So  will  a 
person  drown  in  HO,  not  that  the  water  poisons  him, 
but  because  it  fills  his  lungs,  and  shuts  out  the  air. 
N  does  not  unite  with  any  of  the  metals.  The  insta- 
bility of  all  its  compounds  is  its  striking  peculiarity. 
For  instance,  it  may  be  induced  to  join  its  fortune 
with  iodine,  but  so  gingerly,  that  if  we  even  tread 
heavily  in  the  room  where  it  is  kept,  it  will  leave  its 
partner  in  high  dudgeon,  and  bound  off  into  the  air 
with  a  tremendous  explosion. 

Uses. — RELATION  OF  N  TO  ORGANIC  SUBSTANCES. — 
Four-fifths  of  each  breath  that  enters  our  lungs  is  N ; 
yet  it  comes  out  as  it  went  in,  leaving  the  remaining 
fifth,  O,  to  perform  its  wonderful  mission  within 
our  bodies.  One-fifth  of  our  flesh  is  N,  yet  none  of 
it  comes  from  the  air  we  breathe.  We  obtain  all  our 
supply  from  the  lean  meat  and  vegetables  we  eat. 
Plants  breathe  the  air  through  the  leaves — their 
lungs ;  yet  they  do  not  appropriate  any  of  the  N 
obtained  in  this  way,  but  rely  upon  the  ammonia 
and  nitric  acid  their  roots  absorb  from  the  soil.  N 
enters  the  stove  with  the  O :  the  latter  unites  with 
the  fuel ;  but  the  former,  disdaining  any  such  work, 
passes  on  out  of  the  chimney.  Even  from  a  blast- 
furnace, where  iron  instantly  melts  like  wax,  the  N 


NITROGEN.  33 

* 

comes  forth  without  the  smell  of  fire  upon  it.  So 
unsocial  is  it,  that  it  will  not  affiliate  directly  with 
any  organic  substance.  We  must  all,  animals  and 
plants,  depend  upon  finding  it  bound  hand  and  foot  in 
some  chemical  compound,  and  so  appropriate  it  to 
our  use.  But  even  then  we  hold  it  very  loosely  indeed. 
The  tendency  of  flesh  to  decompose  is  mainly  owing 
to  the  instability  of  the  N  in  its  composition. 

DIFFERENCE  BETWEEN  N  AND  O.* — We  see  now  how 
different  N  is  from  O.  The  one  is  the  conservative 
element,  the  other  the  radical.  But  notice  the  nice 
planning  shown  in  the  adaptation  of  the  two  to  our 
wants.  O,  alone,  is  too  active,  and  must  be  re- 
strained. Were  the  air  pure  O,  our  life  would  be 
excited  to  a  pitch  of  which  we  can  scarcely  dream, 
and  would  sweep  through  its  feverish,  burning  course 
in  a  few  days.  Four  parts  of  the  negative  N  just 
restrain  the  O  within  governable  limits,  adapt  it  to 
our  needs,  and  make  it  our  useful  servant. 

O  AND  N  COMBINED. — Separately,  either  element 
of  the  atmosphere  would  kill  us.  The  fiery  O  and 
the  inert  N  combined  give  us  the  golden  mean.  The 
O  now  quietly  burns  the  fuel  in  our  stoves  and  keeps 
us  warm ;  licks  up  the  oil  in  our  lamps  and  gives  us 
light;  corrodes  our  bodies  and  gives  us  strength; 

*  The  difference  between  these  two  gases  can  be  best  illustrated 
by  having  a  jar  of  each,  and  rapidly  passing  a  lighted  candle  from 
one  to  the  other :  you  will  extinguish  the  light  hi  the  first,  and 
relight  the  coal  in  the  second.  By  dexterous  management  this 
may  be  repeated  a  dozen  times. 

2* 


ELEMENTARY  CHEMISTRY. 


cleanses  the  air  and  keeps  it  fresh  and  invigorating ; 
sweetens  foul  water  and  makes  it  wholesome ;  works 
all  around  and  within  us  a  constant  miracle,  yet  with 
such  delicacy  and  quietness  that  we  never  perceive 
or  think  of  it  until  we  see  it  by  the  eye  of  science. 

NITROUS  OXYD,  NO — LAUGHING  GAS. 
Preparation. — This  gas  is  made  by  heating  nitrate 
of  ammonia.     The  reaction  is  as  follows : 


.  NO5 


O    +    2NO 

The  atom  of  N  and  two  atoms  of  0  from  the  nitric 

acid  unite  with  the 
atom  of  N  from 
the  ammonia, 
forming2NO.The 
four  atoms  of  H 
in  the  ammonia 
unite  with  three 
atoms  of  O  in  the 
nitric  acid  and  the 
one  atom  of  O  in 
the  ammonia, 
forming  4  atoms 


Properties.  —  It  supports  combustion  almost  equal- 
ly with  O,  and,  like  it,  is  colorless  and  odorless.    It 


NITKOUS  OXYD — LAUGHING  GAS.  35 

is  soluble  in  HO,  and  liquefies  at  459F.,  with  a 
pressure  of  50  atmospheres.  It  has  a  sweet  taste, 
and  is  chiefly  noted  for  its  anaesthetic  properties. 

ACTION  ON  HUMAN  SYSTEM. — When  breathed,  it 
produces  a  species  of  intoxication.  The  feeling  is 
generally  one  of  perfect  bliss  and  contentment.  A 
feverish  glow  overspreads  the  body,  and  a  thousand 
delightful  visions  pass  before  the  mind.  The  cares 
and  troubles  of  life 

"  Fold  their  tents  like  the  Arabs, 
And  as  quiet  steal  away." 

A  wild,  delicious,  dreamy  joy  spreads  through  the 
system,  and  annihilates  all  idea  of  time  and  space. 
The  first  inhalation  of  the  gas  sometimes  causes 
bursts  of  laughter,  hysterical  weeping,  or  loud,  un- 
meaning talking.  Then  succeeds  a  glow  of  warmth, 
first  felt  in  the  extremities,  followed  by  a  prickly,  be- 
numbed sensation,  a  confusion  of  ideas,  noises  in  the 
ears  (frequently  compared  to  the  vibration  of  an 
engine  from  one  side  of  the  head  to  the  other),  and 
occasionally  flashes  of  light  before  the  eyes.  With 
this  stage  all  sensation  and  voluntary  motion  cease. 
Without  any  ability  to  act,  one  is  yet  frequently  en- 
tirely conscious  of  all  that  takes  place.  During  this, 
the  anaesthetic  state,  perfectly  painless  operations 
can  be  performed.  Often  the  patient  will  awake,  re- 
membering all  that  has  occurred,  yet  having  felt  no 
pain. 

For  scientific  purposes,   or  for  amusement,   the 


36  ELEMENTABY  CHEMISTRY. 

inhalation  is  stopped  before  the  anaesthetic  stage  is 
reached.  One  can  administer  the  gas  to  himself 
with  perfect  safety  after  a  few  trials.  Before  inhaling, 
he  may  decide  what  he  will  do  while  under  its  influ- 
ence, laugh,  sing,  declaim,  etc. ;  and  keeping  this  idea 
and  no  other  upon  his  mind  while  breathing,  he  will 
find  himself  irresistibly  impelled  to  perform  it.  If 
he  has  no  especial  thought  in  his  mind,  he  is  left  to 
the  inspiration  of  the  moment,  and  may  do  any  ab- 
surd thing  the  occasion  may  suggest,  from  holding 
his  nose  and  bowing  continually  to  the  audience,  to 
clearing  the  stage  of  its  occupants.  The  gas  does 
not  "bring  out  the  natural  disposition  of  the  person," 
as  some  have  believed.  As  soon  as  its  influence 
passes  off,  the  hand  seeks  the  forehead  with  return- 
ing consciousness,  the  eye  resumes  its  natural  ex- 
pression, the  pulse  sinks  to  a  slightly  quickened  beat, 
and  the  dream  is  over. 

EXPLANATION. — The  exciting  effect  of  this  gas  is 
due  to  the  excessive  supply  of  O  it  furnishes  the  sys- 
tem. "When  the  carbonic  acid  gas,  formed  by  this 
unusual  combustion,  accumulates  in  the  veins,  by  its 
narcotic  influence  it  produces  a  temporary  insensi- 
bility. 

Caution. — The  utmost  care  should  be  used  in  pre- 
paring NO.  It  should  stand  over  HO  at  least  12 
hours  before  inhalation,  although  agitation  with  sev- 
eral gallons  of  HO  in  the  gas-bag  is  a  safe  precau- 
tion. No  one  should  ever  breathe  it  who  is  not  in 
good  health  at  the  time,  who  is  troubled  with  a  rush 


NITRIC  ACID. 


37 


of  blood  to  the  head,  any  lung  or  heart  disease,  or 
is  of  a  plethoric  habit.  With  proper  caution,  no  ac- 
cident need  ever  occur. 


NITRIC  ACID  (AQUAFORTIS),  NO5. 

This  acid  is  found  in  nature,  in  combination  with 
soda  or  potash,  and  is  obtained  in  a  separate  state 
by  the  addition  of  a  stronger  acid,  which  drives  off 
the  weaker  and  usurps  its  place.  Thus,  taking 
KO.NO5,  and  adding  SO3,  the  following  chemical 
change  ensues,  while  the  acid  is  collected  in  a  re- 
ceiver, cooled  by  dropping  water  : 


KO.NO5  4-  S03 


KO.SO3 

It  is  formed  in  small  quantities  in  the  atmosphere 
by  the  union  of  its  elements  during  the  passage  of 
electricity,  as  in 
a  thunder-storm, 
and  being  washed 
to  the  earth  by 
rain,  is  absorbed 
by  the  roots  of 
plants. 

Properties. —  It 
is  an  intensely 
corrosive,  poison- 
ous liquid.  When  pure,  it  is  colorless,  but  as  sold, 


Making  NO5 


38  ELEMENTAKY  CHEMISTRY. 

has  commonly  a  golden  color,  from  the  presence  of 
the  red  fumes  of  nitrous  acid,  produced  by  the  de- 
composing action  of  the  light.  It  has  been  obtained 
in  the  form  of  brilliant  transparent  crystals,  but  is 
always  found  dissolved  in  HO,  sometimes  of  twice 
its  own  weight,  never  less  than  J.  In  strength,  it  is 
next  to  SO3.  It  stains  the  skin,  wood,  etc.,  a  bright 
yellow. 

Uses. — It  gives  up  its  O  very  readily,  and  thus 
corrodes  any  substance  with  which  O  will  combine. 
It  is  employed  in  dyeing  woollen  yellow,  and  in  sur- 
gery for  cauterizing  the  flesh.  It  dissolves  most  of 
the  metals,  and  in  combination  with  HC1,  forms  aqua- 
regia,  the  only  solvent  of  gold.  It  etches  the  lines 
in  copperplate  engraving,  and  the  beautiful  designs 
on  the  blades  of  razors,  swords,  and  other  steel 
utensils.  The  process  is  very  simple.  The  surface 
is  covered  with  a  varnish  impervious  to  NO5 ;  the  de- 
sired figure  is  then  sketched  in  the  varnish  with  a 
needle.  The  NO5  being  poured  on,  oxydizes  the 
metal  in  the  delicate  lines  thus  laid  bare. 

ACTION  ON  THE  METALS. — If  a  bit  of  Sn  be  placed 
in  NO5,  the  acid  will  immediately  give  up  to  it  three 
atoms  of  its  O,  making  the  metal  an  oxyd  (SnO2), 
and  reducing  itself  by  the  operation  to  NO2  (nitric 
oxyd) ;  this  passes  off  into  the  air  as  a  gas,  and  eagerly 
seizing  upon  two  atoms  of  O  in  the  air,  becomes 
NO4  (nitrous  acid),  which  we  readily  recognize  by  its 
brilliant,  red-colored  fumes.  If,  instead  of  the  Sn, 
Cu  be  used,  the  action  is  somewhat  different.  A 


NITKIC  ACID. 


39 


portion  of  the  acid  unites  with  the  Cu,  forming  an 
oxyd  (CuOj ;  but  another  portion  instantly  com- 
bines with  CuO,  making  CuO.NO5.  This  we  detect 
by  the  deep  blue  color  it  gives  to  the  liquid.  If  we 
now  evaporate 
the  HO  from  this 
solution,  we  will 
obtain  beautiful 
blue  crystals  of 
the  salt. 

The  experi- 
ment may  be 
performed  with 
the  apparatus 
shown  in  the 
cut.  The  nitric 


Making  NO2 


oxyd,  NO2,  caught  in  the  receiver,  will  be  found  color- 
less, while,  on  admitting  a  bubble  of  air,  blood-red 
fumes  of  NO4  will  fill  the  jar. 

AMMONIA,  NH3.— ^his  gas  is  also  called  hartshorn, 
because  in  England  it  was  formerly  made  from  the 
horns  of  the  hart.  It  received  the  name  ammonia, 
by  which  it  is  now  more  generally  known,  from  the 
temple  of  Jupiter  Ammon,  near  which  sal-ammoniac, 
one  of  its  compounds,  was  once  manufactured.  The 
aqua-ammonia  of  the  shops,  which  is  merely  a  strong 
solution  of  the  gas  in  HO,  is  obtained  from  the  in- 
cidental products  of  the  gas-works  in  large  quanti- 
ties. Water  absorbs  from  400  to  500  times  its  own 
bulk  of  ammonia.  "When  undiluted,  it  will  produce 


40  ELEMENTARY  CHEMISTRY. 

a  blister,  and  should,  therefore,  be  very  much  weak- 
ened before  being  tasted  or  touched.  It  is  a  strong 
alkali,  and  turns  the  vegetable  blues  to  greens ;  but 
owing  to  its  volatility  this  change  of  color  is  only 
temporary.  It  is,  therefore,  sometimes  termed  "  the 
volatile  alkali."  Its  test  is  hydrochloric  acid,  HC1. 
Example  :  If  we  bring  a  stopple  wet  with  HC1  near 
this  gas,  it  will  instantly  reveal  itself  by  a  dense 
cloud  of  white  fumes,  the  chloride  of  ammonium, 
sal-ammoniac,  which  floats  in  the  air  like  smoke. 
The  antidote  of  ammonia  is  vinegar.  Its  pungent 
odor  can  always  be  detected  near  decaying  vegetable 
or  animal  matter.  Smelling-bottles  are  filled  with  a 
mixture  of  finely  powdered  sal-ammoniac  and  lime. 
By  this  method,  ammonia  is  also  made  in  the  arts. 
The  process  is  hastened  by  applying  heat.  The  re- 
action is  as  follows : 

NH4.C1  +  CaO 

rva 

NH3  +  Ca.Cl  +  HO 

One  atom  of  H  of  the  sal-ammoniac  unites  with 
the  O  of  the  lime,  forming  HO.  The  calcium  of  the 
lime  combines  with  the  chlorine,  producing  chloride 
of  calcium,  and  the  NH3  is  set  free  as  a  gas  which 
may  be  absorbed  by  water,  as  in  the  adjoining  illus- 
tration, thus  forming  aqua-ammonia. 

Nascent  state. — If  K  and  H,  the  elements  of  NH3, 
be  mixed  in  a  receiver,  they  will  not  unite  chen> 


NITBIC  ACID. 


41 


Making  NH, 


ically,  owing  to   the  negative  character  of  N,  of 
which  we  have  before  spoken.     "When,  however,  any 
substance    is    decom- 
posed  which  contains 
both  of  them,  as  bit- 
uminous   coal,    flesh, 
etc.,   at  the  very  in- 
,stant  of  their  separa- 
tion from  their  com- 
pounds,  in  the  first 
feeling  of  their  loneli- 
ness, as  it  were,  they  ^1 
will  combine  and  form 
NH3.     This    moment, 
when  elements  are  thus  in  the  act  of  leaving  their 
compounds,  is  called  their  "nascent  state." 

CHLORIDE  OF  AMMONIUM,  MURIATE  OF  AMMONIA,  SAL- 
AMMONIAC,  NH4C1. — In  the  ammoniacal  liquors  just 
named,  and  in  the  distillation  of  horns,  hoofs,  horse- 
flesh, woollen  rags,  etc.,  carbonate  of  ammonia  is 
formed.  By  mixing  this  with  HC1,  that  acid  drives 
off  the  CO2,  and  takes  its  place,  thus  producing 
chloride  of  ammonium.  On  evaporating  the  solu- 
tion, tough,  fibrous  crystals  are  obtained.  They 
reveal  no  trace  of  the  pungent  ammonia,  yet  it  can 
be  easily  set  free,  as  we  have  already  seen.  Sal- 
ammoniac  is  soluble  in  HO  ;  is  used  in  medicine,  and 
also  in  soldering,  the  HC1  it  contains  dissolving  the 
coating  of  the  oxyd  of  the  metal,  and  preserving  the 
surfaces  clear  f  jr  the  action  of  the  solder. 


142 


ELEMENTARY    CHEMISTRY. 


HYDROGEN. 

Symbol,  H  ....  Equivalent,  I  ••••  Specific  Gravity,  .069. 

Hydrogen  means  literally  a  generator  of  water. 

Preparation. — It  is 
always  obtained  by  the 
decomposition  of  HO, 
of  which  it  forms  £ 
part  by  weight.  If  we 
place  in  an  evolution 
flask  (a  common  junk 
bottle  will  answer)  bits 
of  zinc,  and  then  pour 
through  the  funnel 
tube  sulphuric  acid 
(SO3)  and  HO,  the 

gas  will  be  evolved  abundantly.     The  reaction  is  as 

follows : 

Zn  +  SOS  +  HO 


Making  hydrogen. 


ZnO. 


H 


The  zinc  decomposes  the  HO  uniting  with  the  O, 
forming  ZnO,  and  setting  free  the  H,  which  passes 
off  as  a  gas.  But  the  ZnO  would  soon  form  a  coat- 
ing over  the  metal,  and  protect  it  from  the  HO  ;  this 
the  SO3  prevents  by  combining  with  the  ZnO,  form- 
ing ZnO.SO3  (white  vitriol),  and  so  keeping  the  sur- 
face of  the  zinc  bright  and  the  action  constant.  The 


HYDROGEN.  43 

black  specks  which  appear  floating  about  in  the  so- 
lution are  charcoal  from  the  Zn.  The  white  vitriol 
which  is  formed  soon  gives  the  mixture  a  milky -white 
appearance.  By  evaporating  the  HO,  the  crystals 
of  this  salt  can  be  obtained. 

Properties. — H  prepared  in  this  manner  has  a 
disagreeable  odor,  from  various  impurities  in  the 
materials  used.  When  pure,  like  O,  it  is  colorless, 
transparent,  and  odorless.  Its  atoms  are  the  small- 
est of  any  known  element ;  and  in  attempts  made  to 
liquefy  the  gas,  it  leaked  through  the  pores  of  the 
thick  iron  cylinders  in  which  it  was  compressed.  It 
is  the  lightest  of  all  bodies,  being  only  TV  as  heavy 
as  common  air.  It  is  not  poisonous,  although,  like 
N,  it  will  destroy  life  or  combustion  by  shutting  out 
the  life-sustainer,  O.  When  inhaled,  it  gives  the 
voice  a  ludicrously  shrill  tone.  It  can  be  breathed 
for  a  few  moments  with  impunity,  if  it  be  first  passed 
through  lime-water  to  purify  it.  Owing  to  its  light- 
ness, it  passes  out  of  the  lungs  again  directly.  Its 
levity  suggested  its  use  for  filling  balloons,  and  it 
has  been  used  for  that  purpose;*  but  coal  gas, 
which  contains  much  H,  and  is  cheaper,  is  now 
preferred. 

COMBUSTION  OF  H. — A  lighted  candle,  plunged  into 

*  We  read,  in  accounts  of  f£tes  at  Paris,  of  balloons  ingeniously 
made  to  represent  various  animals,  so  that  aerial  hunts  are  de- 
vised. The  animals,  however,  persistently  insist  upon  ascending 
with  their  legs  up — a  circumstance  productive  of  great  mirth  hi 
the  crowd  of  spectators. 


44 


ELEMENTARY   CHEMISTRY. 


an  inverted  jar  of  this  gas,  is  extinguished,  while 
the  gas  itself,  takes  fire,  and  burns  with  a  pale  blue 
flame.  One  atom  of  the  O  of  the  air 
unites  with  an  atom  of  the  H,  and  the 
product  of  the  combustion  is  HO,  which 
may  be  condensed  on  a  cold  tumbler, 
held  over  a  jet  of  the  burning  gas,  as 
in  the  accompanying  figure. 

Mixed  Gases. — A  mixture  of  two  parts, 
by  measure,  of  H,  with  one  part  of  O, 
or  five  parts  of  common  air,  will  ex- 
plode with  a  deafening  report.  The  bulky  gases 
being  instantly  condensed  into  a  mere  drop  of  HO, 
only  y^VjF  as  large,  a  vacuum  is  produced,  and  the 


Candle  in  H. 


Burning  H. 

particles  of  air  rushing  in  to  fill  the  empty  space,  by 
their  collision  against  each  other,  produce  the  stun- 
ning sound.  "While  the  detonation  is  so  great,  the 
force  is  slight,  as  may  be  shown  by  exploding  the 
bubbles  in  the  hand.  The  two  gases  may  be  mingled 
in  the  light  proportion  and  kept  for  years,  and  there 


HYDROGEN.  45 

will  be  no  change.  The  atoms  lie  against  each  other 
quietly,  "  cheek-by-jowl,"  without  any  manifestation 
of  their  chemical  affinity,  when  suddenly,  at  the  con- 
tact of  the  merest  spark  of  fire,  they  rush  together 
with  a  crash  of  thunder,  and  uniting,  form  the  bland, 
passive  liquid — water. 

ACTION  OF  PLATINUM  SPONGE. — A  piece  of  platinum 
sponge  placed  in  a  jet  of  H  will  ignite  it.  This 
curious  effect  seems  to  be  produced  in  the  following 
way :  The  atoms  of  H  and  the  O  of  the  air  are 
brought  so  closely  together  in  its  minute  pores  that 
they  unite,  and  the  heat  thus  produced  sets  fire  to 
the  gas. 

HYDROGEN  TONES.* — A  singular  illustration  of  the 
laws  of  sound  can  be  given  by  simply  holding  a  long 
glass  tube,  by  means  of  a  suitable  clamp,  over  a  minute 
jet  of  burning  H.  At  first  no  effect  will  be  produced ; 
but  as  we  slowly  introduce  the  jet  further  and  fur- 
ther into  the  tube,  a  faint  sound  is  heard,  apparently 

*  Another  illustration  of  singing  hydrogen  may  be  represented 
in  the  following  manner:  Make  a  jar  of  heavy  tin,  in  the  form  of 
a  double  cone,  12  inches  long  and  4  inches  in  diameter.  At  one 
apex  fit  a  nozzle  and  cork,  at  the  other,  make  several  minute 
openings.  Covering  these  openings  with  sealing-wax,  and  draw- 
ing the  cork,  fill  the  jar  with  H,  and  replace  the  cork.  When 
ready  for  use,  hold  the  jar  in  a  vertical  position,  remove  the  wax 
from  at  least  one  orifice,  ignite  the  H  at  that  point,  and  draw  the 
cork.  Still  hold  the  jar  quietly,  and  in  a  minute  or  two  the  tiny 
jet  of  H  will  begin  to  sing  like  a  swarm  of  musquitoes,  buzzing 
and  humming  in  the  most  aggravating  way  until,  most  unex- 
pectedly, the  scientific  music  ends  in  a  loud  explosion. 


46  ELEMENTARY  CHEMISTRY. 

in  the  far-off  distance.  This  gradually  approaches, 
and  finally  bursts  into  a  shrill,  continuous,  musical 
note — the  key-note  of  the  heated  column  of  air 
within  the  tube.  The  cause  of  this  is  thought  to  be 


Hydrogen  Tones. 


that  the  flame  is  momentarily  extinguished  and  re- 
lighted with  a  slight  explosion,  and  these,  rapidly 
repeated,  produce  the  musical  note.  Indeed,  these 
explosions  may  be  made  so  slow  that  the  quivering 


WATER.  47 

of  the  flame  can  be  seen,  and  the  sound  cease  to  be 
continuous  as  before.  Let  us  now  place  the  tube  at 
a  point  where  no  clapping  of  hands  or  unusual  sound 
will  start  it  into  song.  Let  various  tones  be  pro- 
duced from  a  violin,  and  we  will  find  the  flame  re- 
sponding only  to  that  tone  which  is  the  key-note  of 
the  tube,  or  its  octave.  The  violin  player  will  have 
perfect  control  of  this  scientific  music,  and  can  start, 
stop,  or  throw  it  into  violent  convulsions,  even  across 
a  large  hall.  Tubes  of  different  sizes  and  lengths 
will  give  tones  of  diverse  character  and  pitch.  The 
waves  of  sound  from  the  instrument  augmenting  or 
interfering  with  those  in  the  tube  will  probably  ac- 
count for  these  phenomena. 

WATER. 

Symbol,  HO-..- Equivalent,  9-.-- Freezes  at  32°F Boils  at  2f2°F. 

The  composition  of  HO  is  proved  by  analysis  and 
synthesis — i.  e.t  by  separating  the  compound  into  its 
elements,  and  by  combining  the  elements  to  produce 
the  compound.  We  can  analyze  it  in  the  manner 
already  shown  in  preparing  H,  or  by  passing  through 
it  a  galvanic  current,  when  the  O  will  appear  in 
bubbles  of  gas  at  the  positive  pole,  and  the  H  in  a 
similar  way  at  the  negative.  In  the  synthetic  method, 
we  mix  the  two  gases,  and  unite  them  as  we  have 
before  by  an  electric  spark.  The  blacksmith  decom- 
poses water  when  he  sprinkles  it  on  the  hot  coals  in 
his  forge.  The  H  burns  with  a  blue  flame,  while  the 


48  ELEMENTARY  CHEMISTKY. 

O  increases  the  combustion.  Thus,  in  a  fire,  if  the 
engines  throw  on  too  little  water,  it  will  be  decom- 
posed, and  so  add  to  the  fury  of  the  flame.  To  "  set 
the  North  River  on  fire"  is  only  a  poetical  exagger- 
ation. 

The  quantity  of  electricity  required  to  decompose 
a  single  grain  of  water  is  estimated  to  be  equal  to 
a  powerful  flash  of  lightning.  The  enormous  force 
necessary  to  tear  these  two  elements  from  each  other 
shows  the  wonderful  strength  of  chemical  attraction. 
We  thus  see,  that  in  a  tiny  drop  of  dew  there,  slum- 
bers the  latent  power  of  a  thunderbolt. 

WATER  IN  THE  ANIMAL  WORLD. — The  abundance 
of  water  very  forcibly  attracts  the  attention.  It  con- 
stitutes four-fifths  of  our  flesh  and  blood.  Man  has 
been  facetiously  described  as  12  Ibs.  of  solid  matter 
wet  up  in  six  pails  of  water.  All  plumpness  of  flesh, 
all  fairness  of  the  cheek,  are  given  by  the  juices  of 
the  system.  A  few  ounces  of  water  causes  the  phys- 
ical difference  between  the  round,  rosy  face  of  six- 
teen, and  the  wrinkled,  withered  features  of  three- 
score and  ten.  Our  tears,  poetical  as  they  may  seem 
to  us  sometimes,  are  only  water  and  a  pinch  of  salt. 
To  supply  the  wants  of  the  system  each  man  needs 
about  |  of  a  ton  annually.  When  we  pass  to  lower 
orders  of  animals,  we  find  this  liquid  still  more  abun- 
dant. Sunfishes  are  little  more  than  organized  water. 
Professor  Agassiz  analyzed  one  found  off  the  coast 
of  Massachusetts,  which  weighed  30  Ibs.,  and  ob- 
tained only  J  an  ounce  of  dried  flesh.  Indeed, 


WATEK.  49 

naturalists  state  that  an  entire  order  of  animals  (aca- 
lephs),  belonging  to  which  are  the  jelly-fish,  medusa, 
etc.,  is  composed  of  only  ten  parts  in  a  thousand  of 
solid  matter. 

WATER  IN  THE  VEGETABLE  WORLD. — In  the  vege- 
table world  we  find  it  abundant.  Wood  is  composed 
of  12  parts  charcoal  and  10  parts  water,  with  a  little 
mineral  matter  comprising  the  ashes.  Bread  is  half 
water ;  and  of  the  potatoes  and  turnips  cooked  for 
our  dinner,  it  comprises  75  parts  of  one  and  90  of 
the  other.  The  following  table  shows  the  proportion 
in  common  vegetables,  fruits,  and  meats  : 


Mutton.  ., 

,  .  .71 

Trout 

.81 

Cabbage  92 

Beef 

74 

Apples.  .  .  . 

.80 

Cucumbers  .  .97 

Veal 

75 

Carrots  .  .  . 

.83 

Watermelons  .98 

Pork 

.76 

Beets  .  . 

.88 

In  all  these  instances  water  is  essential  to  the  struc- 
ture and  constitution  of  the  various  substances. 
Eemove  it,  and  they  are  decomposed  into  entirely 
new  compounds. 

WATER  IN  THE  MINERAL  WORLD. — Here  we  find  a 
class  of  bodies  in  which  the  water  is  chemically  com- 
bined in  definite  proportions.  Such  are  called  hy- 
drates. In  the  image  which  the  Italian  pedler 
carries  through  our  streets  for  sale,  there  is  1  Ib.  of 
HO  to  every  4  Ibs.  of  plaster  of  Paris.  One-third  of 
the  weight  of  the  soil  of  our  farms  is  this  same 
liquid.  Each  pound  of  strong  NO5  contains  2  J  oz.  of 
water,  .which,  if  removed,  would  destroy  the  acid 

3 


50  ELEMENTARY  CHEMISTRY. 

itself.  If  we  expel  the  water  from  oil  of  vitriol,  it 
will  lose  its  acid  properties,  and  we  can  handle  it 
with  impunity.  In  bodies  which  are  capable  of  crys- 
tallizing, it  seems  only  to  determine  the  form  and 
general  appearance,  and  is  called  "  the  water  of  crys- 
tallization." If  we  evaporate  this  from  blue  vitriol, 
it  will  lose  its  color  and  become  white  like  flour.  A 
few  drops  of  HO  will  restore  the  blue.  If  we  expel 
it  from  alum,  it  will  puff  up,  and  the  transparent 
crystals  will  dry  into  an  incoherent  mass.  Water 
of  crystallization  gives  all  the  transparency  to  the 
opal,  which  else  would  be  only  common  flint-stone. 

WATER  AS  A  SOLVENT. — Water,  having  no  taste, 
color,  or  odor  itself,  is  perfectly  adapted  to  become 
the  universal  solvent,  receiving  instantly  the  charac- 
teristics of  any  substance  placed  in  it.  It  becomes 
at  pleasure  sweet,  sour,  salt,  bitter,  nauseous,  and 
even  poisonous.  Had  water  any  taste,  the  whole 
science  of  cookery  would  be  changed,  since  each 
substance  would  partake  of  the  one  universal  watery 
flavor. 

PURE  WATER. — Bain-water,  caught  after  the  air  is 
thoroughly  cleansed  by  previous  showers,  and  at  a 
distance  from  the  smoke  of  cities,  is  the  purest  nat- 
ural water  known.  This  is  tasteless,  yet  its  insi- 
pidity makes  it  seem  to  us  very  ill-flavored  indeed. 
We  have  become  so  accustomed  to  the  taste  of  the 
impurities  in  hard  water,  that  they  have  become  to 
us  tests  of  its  sweetness  and  pleasantness. 

HARD  WATER. — As  water  filters  down  through  the 


WATER.  51 

soil  into  our  wells,  it  dissolves  the  various  mineral 
matters  characteristic  of  the  locality.  The  most 
common  of  these  are  lime,  salt,  and  magnesia.  The 
former  produces  a  fur  or  coating  on  the  bottom  of 
our  teakettles,  if  we  live  in  a  limestone  region. 
When  we  put  soap  in  such  water,  it  curdles — i.  e.,  it 
unites  with  the  lime,  forming  a  new  or  lime  soap, 
which  is  insoluble  in  HO. 

SEA- WATER. — Common  salt  is  the  most  abundant 
mineral  in  the  ocean.  Yet  it  contains  traces  of  every 
substance  soluble  in  water,  which  has  been  washed 
into  the  sea  from  the  surface  of  the  continents  during 
all  the  ages  of  the  past.  Its  saline  constituents  are 
now  in  the  proportion  of  about  a  ^  oz.  to  a  lb.,  which 
amount  must  be  slowly  increasing,  as  the  water 
which  evaporates  from  the  surface  is  comparatively 
pure,  containing  only  a  mere  trace  of  a  few  sub- 
stances, which  give  to  the  sea-breeze  its  peculiar 
bracing,  tonic  influence.  In  this  way,  the  water  of 
the  Salt  Lake  has  become  the  strongest  of  brine, 
nearly  one-third  of  its  whole  weight  consisting  of 
saline  matter.  This  condition  would  soon  disappear 
if  an  outlet  could  be  provided. 

WATER  ATMOSPHERE. — As  the  world  of  waters  is 
inhabited,  it  has  its  atmosphere  also.*  Inasmuch  as 
the  HO  dilutes  the  O  in  part,  it  does  not  need  so 

*  Fish  breathe  O  through  the  fine  silky  filaments  of  their  gills 
When  a  fish  is  drawn  out  of  HO,  these  dry  up,  and  he  is  unable 
to  breathe,  although  he  is  in  a  more  plentiful  atmosphere  than  he 
is  accustomed  to  enjoy. 


52  ELEMENTAEY  CHEMISTRY. 

much  N  as  the  common  air.  It  is  accordingly  com- 
posed of  ^  O  instead  of  ^.  The  air  so  rich  in  O  thus 
absorbed  by  the  water  gives  it  its  life  and  briskness. 
If  it  be  expelled  by  boiling,  the  water  tastes  flat  and 
insipid. 

PARADOXES  OF  HO. — "  Cold  contracts,"  is  the  law 
of  physics ;  but  as  HO  cools,  it  obeys  this  principle 
only  as  far  as  39°  F.  Then  it  slowly  expands,  cool- 
ing down  to  32°,  its  freezing  point,  when  its  crystals 
suddenly  dart  out  at  angles  to  each  other,  and  thus, 
increasing  its  size  -fa,  it  congeals  to  ice.  By  this 
wise  exception,  ice  is  lighter  than  HO,  and  so 
swims  on  top ;  otherwise  our  rivers  would  freeze 
solid,  killing  the  fish  and  aquatic  plants.  The  longest 
summer  could  not  melt  such  an  immense  mass  of  ice. 
But  now  the  blanket  that  nature  kindly  weaves  over 
the  rivers  and  ponds  keeps  their  finny  inhabitants 
warm  and  comfortable  till  spring ;  then  she  floats  it 
south  to  melt  under  a  hotter  sun.  Water  is  full  of 
contradictory  terms.  We  have  hard  water  and  soft 
water,  fresh  water  and  salt  water.  Water  seems  the 
most  yielding  of  substances,  yet  the  swimmer  who 
falls  on  his  face  instead  of  striking  head  foremost 
understands  the  mistake,  and  we  could  drive  a  nail 
into  a  solid  cube  of  steel  easier  than  into  a  hollow  one 
perfectly  filled  with  HO.  H  is  the  lightest  substance 
known,  and  O  is  an  invisible  gas ;  yet  they  unite  and 
form  a  liquid  whose  weight  we  have  often  experienced, 
and  a  solid  which  makes  a  pavement  as  hard  and 
unyielding  as  granite.  H  burns  readily  and  explodes 


WATER.  53 

most  fearfully,  O  supports  combustion  brilliantly — 
yet  the  two  combined  are  used  to  extinguish  fires. 

USES  OF  WATER. — The  uses  of  water  are  as  poetical 
as  they  are  practical.  Its  properties,  already  dis- 
cussed in  Natural  Philosophy,  of  specific  heat,  of  ex- 
panding as  it  solidifies,  together  with  that  we  have 
just  named  of  dissolving  such  a  wide  range  of  gases 
and  solids,  fit  it  for  a  wonderful  variety  of  opera- 
tions in  nature.  Its  office  is  not  merely  to  moisten 
our  lips  on  a  hot  day,  to  make  a  cup  of  strong  tea, 
to  lay  the  dust  in  the  street,  and  to  sprinkle  our  gar- 
dens. It  has  grander  and  more  profound  uses  than 
any  of  these.  Water  is  the  common  carrier  of  crea- 
tion. It  dissolves  the  elements  of  the  soil,  and 
climbing  as  sap  up  through  the  delicate  capillary 
pump  of  the  plant,  furnishes  the  leaf  with  the  ma- 
terials of  its  growth.  It  flows  through  the  body  as 
blood,  floating  to  every  part  of  the  system  the  life- 
sustaining  O,  and  the  food  necessary  for  repairs  and 
for  building  up  the  various  parts  of  the  "  house  we 
live  in."  It  comes  in  the  clouds  as  rain,  bringing  to 
us  the  heat  of  the  tropics,  and  tempering  our  north- 
ern climate,  while  in  spring  it  floats  the  ice  of  our 
rivers  and  lakes  away  to  warmer  seas  to  be  melted. 
It  washes  down  the  mountain  side,  levelling  its  lofty 
summit  and  bearing  mineral  matter  to  fertilize  the 
valley  beneath.  It  propels  water-wheels  working 
forges  and  mills,  and  thus  becomes  the  grand  motive- 
power  of  the  arts  and  manufactures.  It  flows  to  the 
sea,  bearing  on  its  bosom  ships  conducting  the  com- 


54  ELEMENTARY   CHEMISTRY. 

inerce  of  the  world.  It  passes  through  the  arid 
sands,  and  the  desert  forthwith  buds  and  blossoms 
as  the  rose.  It  limits  the  bounds  of  fertility,  decides 
the  founding  of  cities,  and  directs  the  flow  of  trade 
and  wealth. 

CARBON. 

Symbol,  C  ••••  Equivalent,  8. 

Carbon  is  one  of  the  most  abundant  substances  in 
nature,  forming  nearly  one-half  of  the  entire  vege- 
table kingdom,  and  being  a  prominent  constituent 
of  limestone,  corals,  marble,  magnesian  rocks,  etc. 
We  find  it  in  three  distinct  forms  or  allotropic  con- 
ditions— viz.,  the  diamond,  graphite,  and  amorphous 
carbon.  This  last  term  means  without  form  or  crys- 
tals, and  includes  gas-carbon,  charcoal,  lamp-black, 
coal,  coke,  peat,  soot,  bone-black  and  ivory-black. 
In  each  of  these  various  substances  C  possesses  dif- 
ferent properties ;  yet  any  impurities  it  may  contain 
seem  entirely  incidental,  and  not  at  all  necessary  to 
its  new  state. 

PROOF  OP  THIS  ALLOTROPIC  STATE. — Chemists  have 
changed  most  of  these  substances  into  other  allo- 
tropic forms.  Thus,  common  charcoal  has  been 
turned  into  graphite,  mineral  coal  into  gas-carbon, 
the  diamond  into  coke.  All  of  them,  when  heated 
in  the  open  air,  unite  with  the  same  quantity  of  O, 
forming  precisely  the  same  compound  —  carbonic 
acid  gas — from  which  the  carbon  can  be  obtained 
again  in  the  form  of  charcoal. 


CAKBON.  55 

THE  DIAMOND  is  pure  carbon  crystallized.  It  is 
the  hardest  of  all  known  substances,  scratches  all 
other  minerals  and  gems,  and  can  be  cut  only  by  its 
own  dust.  It  is  infusible,  but  will  burn  at  a  high 
temperature.  It  is  found  in  various  parts  of  the 
world — North  Carolina,  Georgia,  Borneo,  and  Brazil. 
The  ancient  mines  of  Golconda,  in  Hindostan,  are 
not  now  worked.  In  1858,  Brazil  furnished  120,000 
carats.*  Diamonds  are  supposed  to  be  of  vegetable 
origin,  and  to  have  exuded,  at  some  past  time,  as 
gum  does  now  from  cherry-trees,  and  then  slowly 
crystallized.  When  found,  they  look  like  round 
pebbles,  and  are  covered  with  a  thin  crust,  which 
being  broken  reveals  the  brilliant  gem  within.  They 
are  of  various  colors,  though  often  colorless  and  per- 
fectly transparent.  The  latter  are  most  highly 
esteemed,  and,  from  their  resemblance  to  a  drop  of 
clear  spring-water,  are  called  diamonds  of  the  "  first 
water." 

THE  DIAMOND  is  GROUND  by  means    of  its  6wn 
powder.     Being  fitted  to  the  end  of  a  stick  or  handle, 
it  is  pressed  down  firmly  against  the  face  of  a  rapidly 
revolving    wheel,    covered  with 
diamond-dust  and  oil.     This,  by 
its  friction,  removes  the  exposed 
edge  and  forms  a  facet  of  the  The  briuiant    The  r08e' 
gem.    There  are  three  forms  of  cutting — the  brilliant, 

*  A  carat  is  equal  to  4  gr.  Troy.  The  term  is  derived  from  the 
name  of  a  bean  which,  when  dried,  was  formerly  used  by  diamond 
merchants  in  India  as  weights. 


58  ELEMENTARY  CHEMISTRY. 

wood,  covered  over  with  turf,  so  as  to  prevent  free 
access  of  air.  The  volatile  gases,  water,  etc.,  are 
driven  off,  and  the  C  left  behind.  This  forms  about 
J  of  the  bulk  of  the  wood  and  |  its  weight.  Char- 
coal for  gunpowder  and  for  medicinal  purposes  is  pre- 
pared by  heating  willow  or  black  alder  in  iron  retorts. 
Properties. — It  is  the  most  unchangeable  of  all 
the  elements,  so  that  even  in  the  charcoal  we  can 
trace  all  the  delicate  structure  of  the  plant  of  which 
it  was  made.  It  is  insoluble  in  any  liquid.  None 
of  the  acids,  except  nitric,  corrode  it.  No  alkali  will 
eat  it.  Neither  air  nor  moisture  affects  it.  Wheat 
has  been  found  in  the  ruins  of  Herculaneum  that 
was  charred  1800  years  ago,  and  yet  the  kernels  are 
as  perfect  as  if  grown  last  harvest.  The  ground  end 
of  posts  are  rendered  durable  by  charring.  Indeed 
some  were  dug  up  not  long  since  in  the  bed  of  the 
Thames  which  were  placed  there  by  the  ancient  Brit- 
ons to  oppose  the  passage  of  Julius  Caesar  and  his 
army.  A  cubic  inch  of  fine  charcoal  has  100  feet  of 
surface,  so  full  is  it  of  minute  pores.  These  absorb 
gases  by  capillary  attraction  to  an  almost  incredible 
extent.  A  bit  of  C  will  take  up  90  times  its  bulk  of 
ammonia.  As  the  various  gases  and  the  O  of  the 
air  are  brought  so  closely  together  within  its  pores, 
rapid  chemical  changes  are  produced,  as  in  the  case 
of  platinum  black,  of  which  we  have  already  spoken. 
Fresh  provisions  are  packed  in  C  for  long  voyages, 
and  hams  have  been  thus  kept  sweet  for  years.  Foul 
water  filtered  through  C  loses  its  impurities.  Beer 


CARBON.  59 

by  this  process  parts  not  only  with  its  color  but  with 
its  bitter  taste.  Ink  is  robbed  of  its  value  and  comes 
out  clear  and  transparent  as  water. 

Deoxydizing  Action  of  C. — At  a  high  tempera- 
ture the  appetite  of  C  for  O  is  insatiable.  It  will 
take  it  out  in  the  heat  of  a  furnace  from  almost  the 
stablest  compounds.  Upon  this  fact  depends  it  use 
in  the  arts.  Nearly  all  the  ores  and  many  of  the  ele- 
ments are  locked  up  in  the  rocks  with  O,  and  C  is  the 
key  expressly  made  by  the  Creator  for  unlocking  the 
treasure-houses  of  nature  for  the  supply  of  our  wants. 
By  noticing  the  process  of  preparing  zinc,  iron,  phos- 
phorus, etc.,  we  shall  see  the  importance  of  this 
property  of  C.  A  very  pretty  illus- 
tration is  shown  by  placing  a  few 
grains  of  litharge  (PbO),  or  the 
oxyd  of  any  metal,  on  a  flat  piece  of  Litharge  on  charcoah 
charcoal,  and  directing  upon  it  the  flame  of  a  blow- 
pipe. The  metal  will  immediately  appear  in  little 
sparkling  globules. 

SOOT  is  unburnt  carbon  which  passes  off  from  a 
lamp  or  fire  when  there  is  not  enough  O  present  to 
combine  with  all  the  C  of  the  fuel.  This,  therefore, 
comes  away  in  flakes,  and  blackens  the  chimney  of 
the  lamp,  or  lodges  in  the  chimney  of  the  house. 
After  a  time  it  gathers  in  sufficient  quantity,  and  we 
are  startled  by  the  cry,  "  The  chimney  is  on  fire !" 
while  with  a  great  roar  and  flame  the  soot  burns  out. 
This  unpleasant  occurrence  is  much  more  frequent 
when  green  wood  is  used  for  fuel.  The  HO  of  the 


60  ELEMENTARY  CHEMISTRY. 

wood  absorbs  much  of  the  heat  of  the  fire,  and  so 
permits  the  C  to  pass  off  unconsumed. 

LAMPBLACK  is  obtained  by  imperfectly  burning 
pitch  or  tar.  The  dense  cloud  of  smoke  is  conducted 
into  a  chamber  lined  with  sacking,  upon  which  the 
soot  collects.  It  is  largely  used  in  painting.  It  is 
mixed  with  clay  to  form  black  drawing-crayons,  and 
with  linseed  oil  to  make  printers'  ink.  Lampblack 
or  charcoal  has  peculiar  properties  which  fit  it  for 
printing.  Nothing  in  nature  could  supply  its  place. 
No  matter  how  finely  it  is  pulverized,  it  retains  its 
dead-black  color.  The  minutest  particle  is  as  black 
as  the  largest  mass.  No  chemical  agents  will  change 
it.  It  never  decays.  The  paper  may  moulder — we 
may  even  burn  it,  and  still,  in  the  ashes,  can  we  trace 
the  form  of  the  printed  letter.  The  ancients  used  an 
ink  composed  of  gum-water  and  lampblack,  and  man- 
uscripts have  been  exhumed  from  the  ruins  of  Pom- 
peii^and  Herculaneum  which  are  yet  perfectly  legible. 

ANIMAL  CHARCOAL,  or  bone-black,  is  made  by  burn- 
ing bones  in  close  vessels.  Mixed  with  oil  of  vitriol, 
it  forms  paste-blacking.  Common  vinegar  filtered 
through  it  becomes  the  colorless  white  vinegar  of  the 
pickle  manufacturers.  It  is  largely  used  by  sugar 
refiners.  Brown  sugar  is  dissolved  in  HO,  and  the 
solution  filtered  through  animal  charcoal.  This  re- 
moves all  the  impurities  which  constitute  the  color- 
ing matter.  The  solution  is  then  slowly  evaporated 
in  "  vacuum  pans,"  and  the  sugar  collects  in  clear 
white  crystals. 


CARBON.  61 

MINERAL  COAL. — This  was  formed  in  a  former 
period  of  the  world's  history,  called  the  Carboniferous 
Era.  At  that  time  the  world  was  pervaded  by  a 
genial  tropical  climate.  The  air  was  denser  and 
richer  with  vegetable  food  than  now.  The  earth 
itself  was  a  swamp,  moist  and  hot,  in  which  plants 
that  creep  at  our  feet  to-day,  or  are  known  only  as 
rushes  or  grasses,  grew  to  the  height  of  lofty  trees, 
and  simple  ferns  towered  into  trunks  a  foot  and 
a  half  in  diameter.  These  fern-forests  resounded 
with  no  song  of  bird  or  hum  of  insect ;  but  a  strange 
and  grotesque  vegetation  flourished  with  more  than 
tropical  luxuriance.  In  these  swamps  accumulated 
a  vast  deposit  of  leaves  and  fallen  trunks  which, 
under  the  water,  gradually  changed  to  charcoal.  In 
the  process  of  time  the  earth  settled  at  various  points, 
and  floods  poured  in,  bringing  sand,  pebbles,  clay, 
and  mud,  filling  up  all  the  spaces  between  the  trees 
that  were  standing,  and  even  the  hollow  trunks  them- 
selves. The  pressure  of  this  soil  and  the  internal 
heat  of  the  earth  combined  to  expel  the  gases  from 
the  vegetable  deposits,  and  convert  them  into  min- 
eral coal.  "Where  this  process  was  nearly  complete, 
anthracite  coal,  and  where  only  partially  finished, 
bituminous  coal,  was  formed.  The  greater  the  pres- 
sure, the  harder  and  purer  the  carbon  produced ;  un- 
less, however,  the  covering  was  not  sufficiently  porous 
to  allow  the  gases  to  escape,  when  bituminous  coal 
was  the  result.  In  time  this  section  was  elevated 
again,  and  another  forest  flourished,  to  be  in  its  turn 


62  ELEMENTARY  CHEMISTRY. 

converted  into  coal.  Each  of  these  alternate  eleva- 
tions and  depressions  produced  a  layer  of  coal  or  of 
soil.  In  these  beds  of  coal  we  now  find  the  trunks 
of  trees,  the  outlines  of  trailing  vines,  the  stems  and 
leaves  of  plants  as  perfectly  preserved  as  in  a  her- 
barium, so  that,  to  the  botanist,  the  flora  of  the  Car- 
boniferous era  is  as  complete  as  that  of  our  own. 

COKE  is  the  refuse  of  gas-works,  obtained  by  dis- 
tilling off  all  the  water,  tar,  and  volatile  gases  from 
bituminous  coal.  It  is  burned  in  locomotives,  blast- 
furnaces, etc. 

PEAT  is  an  accumulation  of  half-decomposed  veg- 
etable matter  in  swampy  places.  It  is  produced 
mainly  by  a  kind  of  moss  which  gradually  dies  below 
as  it  grows  above,  and  thus  forms  beds  of  great  thick- 
ness. Sometimes,  however,  plants  may  grow  in  the 
form  of  a  turf,  and  decay,  thus  collecting  a  vast  amount 
of  vegetable  debris.  This  gradually  undergoes  a 
change,  and  becomes  a  brownish  black  substance, 
loose  and  friable  in  its  texture,  resembling  coal,  but, 
unlike  it,  containing  20  to  30  per  cent,  of  O.  These 
peat-beds  are  of  vast  extent.  One-tenth  of  Ireland 
is  covered  by  them.  One,  near  the  mouth  of  the 
River  Loire,  is  said  to  be  fifty  leagues  in  circumfer- 
ence. In  Massachusetts  and  in  New  York  peat  is 
becoming  of  commercial  value,  and  is  used  as  a  fuel 
in  large  quantities.  For  this  purpose  it  is  cut  out  in 
square  blocks  and  dried  in  the  sun.  In  many  beds 
it  is  first  finely  pulverized,  then  pressed  into  a  very 
compact  form  like  brick. 


CARBON.  63 

MUCK  is  an  impure  kind  of  peat,  not  so  fully  car- 
bonized, though  the  term  is  frequently  applied  to  any 
black  swampy  soil  which  contains  a  large  quantity 
of  decaying  vegetable  matter.  Like  charcoal,  it  ab- 
sorbs moisture  and  gases,  and  is  therefore  used  as  a 
fertilizer. 

VARIOUS  FORMS  AND  USES  OF  CARBON. — We  have 
seen  in  what  contrary  forms  carbon  presents  itself. 
It  is  soft  enough  for  the  pencil-sketch,  and  hard 
enough  for  the  glazier's  use.  Black  and  opaque,  it 
expresses  thought  on  the  printed  page :  clear  and 
brilliant,  it  gleams  and  flashes  in  the  diadem  of  a 
king.  In  lampblack  it  frequently  takes  fire  spon- 
taneously; in  graphite,  it  resists  the  heat  of  the 
fiercest  flame;  in  the  diamond,  it  is  an  insulator, 
while  in  charcoal,  it  is  so  perfect  a  conductor  of  elec- 
tricity, that  it  is  packed  about  the  foot  of  lightning- 
rods  to  complete  the  connection  with  the  earth.  We 
burn  it  in  our  lamps,  and  it  gives  us  light ;  we  burn 
it  in  our  stoves,  and  it  gives  us  heat ;  we  burn  it  in 
our  engines,  and  it  gives  us  power ;  we  burn  it  in  our 
bodies,  and  it  gives  us  strength.  As  fuel,  it  readily 
unites  with  O,  yet  we  spread  it  as  stove-polish  on 
our  ironware  to  keep  the  metal  from  rusting.  It 
gives  firmness  to  the  tree  and  consistency  to  our 
fiesh.  It  is  the  valuable  element  of  all  fuel,  burning 
oils,  and  gases.  Thus  it  supplies  our  wants  in  the 
most  diverse  manner,  illustrating  in  every  'phase  the 
forethought  of  that  Being  who  fitted  up  this  world  as 
a  ho  ne  for  his  children.  Infinite  Wisdom  alone  would 


64  ELEMENTAKY  CHEMISTBT. 

have  stored  up  such  supplies  of  fuel  and  light,  and 
hidden  them  far  under  the  earth  away  from  all  dan- 
ger of  accidental  combustion,  or  anticipated  all  the 
requirements  alike  of  luxury  and  the  arts. 

CARBONIC  ACID. 

Symbol,  C02  ••••  Equivalent,  22  ...-Specific  Gravity,  1.52. 

Sources. — It  is  found  combined  with  lime,  as  in  lime- 
stone, marble,  chalk,  and  also  in  a  large  class  of  salts, 
known  as  the  carbonates,  forming  nearly  one-half  of 
their  weight,  and  almost  one-seventh  of  the  crust  of 
the  earth.  It  comprises  y^g-  part  of  the  atmosphere. 
It  is  produced  throughout  nature  in  immense  quan- 
tities. Wherever  C  burns,  in  fires,  lights,  decay, 
fermentation,  volcanoes — in  a  word,  in  all  those  va- 
rious forms  of  combustion  of  which  we  spoke  under 
the  subject  of  O,  where  that  gas  unites  with  C,  car- 
bonic gas  is  the  result.  Each  adult  exhales  about 
140  gallons  per  day.  Each  bushel  of  charcoal,  in 
burning,  produces  2500  gallons. 

Preparation. — For  experimental  purposes  it  is  pre- 
pared by  pouring  HC1  (hydrochloric  acid)  on  marble 
or  chalk.  The  reaction  is  as  follows  : 

HC1  4-  CaO.C02 


CaCl  +  C02 


The  H  of  the  hydrochloric  acid  unites  with  the  O 
of  the  lime  (CaO),  forming  HO.     The  01  of  the  acid 


CARBONIC  ACID.  65 

combines  with  the  Ca  of  the  lime,  forming  chloride 
of  calcium,  while  the  C02  is  driven  off.     It  may  be 


Making  carbonic  acid. 

collected  in  bottles  by  displacement,  or  as  represented 
in  the  cut. 


Pouring  CO9  down-hill. 


66 


ELEMENTAEY  CHEMISTRY. 


Test. — Its  test  is  clear  lime-water.  If  we  expose 
a  saucer  of  lime-water  to  the  air,  its  surface  is  soon 
covered  with  a  thin  pellicle  of  carbonate  of  lime,  thus 
showing  that  there  is  CO2  in  the  atmosphere ;  or  if 
we  breathe  by  means  of  a  tube  through  lime-water, 
the  solution  will  become  turbid  and  milky,  thus  prov- 
ing the  presence  of  CO2  in  our  breath :  by  breathing 
through  the  liquid  a  little  longer  it  will  become  clear, 
as  the  carbonate  of  lime  will  dissolve  in  an  excess 
of  CO2. 

Properties. — It  is  a  colorless,  odorless,  transparent 
gas,  with  a  slightly  acid  taste.  It  is  a  non-supporter 
of  combustion,  will  run  down  an  inclined  plane,  and 
can  be  poured  from  one  dish  to  another,  and  dipped 
up  with  a  bucket  like  water,  or  be  weighed  in  a  pair 
of  scales  like  lead.  Example  :  The  accompanying 


Weighing  CO3. 


cut  shows  a  very  neat  way  of  illustrating  several  of 
these  properties.  For  weighing,  the  C02  may  be 
contained  in  a  large  paper  box  or  bag,  such  as  is 
used  by  grocers. 


CARBONIC  ACID. 


67 


Poisoning  by  C02- — This  gas  is  fatal  to  life.  When 
largely  diluted  it  acts  as  a  narcotic,  producing  lan- 
guor, and  finally  insensibility  and  death.  It  accu- 
mulates in  wells  and  cellars,  and  many  persons  have 
been  poisoned  by  descending  into  such  places  incau- 
tiously. The  test  of  lowering  a  lighted  candle  should 

always  be  employed.   If  that 

is    extinguished,    your    life 

would  be  in  danger  of  "  go- 
ing out"  in  the  same  way, 

should  you    descend.     The 

gas  may  be  dipped  out  like 

water,  or   the  well  may  be 
Canodfco2.jar  purified  by  lowering  pans  of 

slacked  lime,  or  lighted  coals  A  candle  ta  c°a' 
which,  when  cool,  will  absorb  the  noxious  gas.  The 
coals  may  be  reignited,  and  lowered  repeatedly  until 
the  result  is  reached.  A  well,  in  which  a  candle 
would  not  burn  within  26  feet  of  the  bottom,  was 
thus  purified  in  a  single  afternoon.  Persons  have 
been  poisoned  by  burning  charcoal  in  an  open  fur- 
nace in  a  closed  room.  In  Prance,  it  is  not  unusual 
to  commit  suicide  in  this  manner.  The  antidote  is 
to  bring  the  sufferer  into  the  fresh  air,  and  dash  cold 
water  upon  his  face.  In  the  celebrated  Grotto  dd 
Cane,  in  Italy,  the  gas  accumulates  near  the  floor,  so 
that  a  man  living  near  amuses  visitors,  for  a  small 
fee,  by  leading  his  dog  into  the  cave.  He  experi- 
ences no  ill  effects  himself,  but  the  dog  soon  falls 
senseless,  A  dash  of  cold  water  revives  him,  and 


68  ELEMENTARY  CHEMISTRY. 

he  is  ready  to  pick  up  his  bone  and  enjoy  the  reward 
of  his  scientific  experiment.  The  celebrated  Upas 
tree  of  Java  seems  not  to  be  altogether  fabulous. 
The  poison  is  not  derived  from  the  tree  itself ;  but 
is  due  to  the  fact  that  it  is  located  in  a  deep  valley 
about  a  half-mile  in  circumference,  in  which  CO2  is 
evolved  in  quantities  sufficient  to  contaminate  the 
entire  atmosphere.  The  valley  is  said  to  be  strewn 
with  the  bones  of  animals  and  birds  which  have 
strayed  into  this  gaseous  lake. 

CO 2,  in  Mines. — Miners  call  CO2  clioke-damp.  It 
is  produced  by  the  explosion  (Afire-damp  (light  car- 
buretted  hydrogen)  which  accumulates  in  deep  mines, 
and  burns  with  a  shock  like  gunpowder,  forming  dense 
volumes  of  CO2,  which  instantly  destroys  the  lives  of 
all  who  may  have  escaped  the  flames  of  the  explosion. 
Where  CO2  alone  is  found,  it  is  not  considered  as  dan- 
gerous as  the  fire-damp,  since  it  will  not  burn,  and  it 
is  said  that  miners  will  even  venture  "  where  the  air  is 
so  foul  that  the  candles  go  out,  and  are  then  relighted 
from  the  flame  on  the  wick  by  swinging  them  quickly 
through  the  air,  when  they  burn  a  little  while  and 
then  go  out,  and  are  relighted  in  the  same  way." 
CO2  has  been  used  for  the  purpose  of  extinguishing 
fires  in  coal-mines.  In  one  case  an  English  mine 
had  burned  for  20  years,  consuming  a  seam  of  coal 
over  a  space  of  26  acres,  defying  all  attempts  to 
quench  it.  8,000,000  cubic  feet  of  CO2  were  poured 
into  it  day  and  night  for  three  weeks,  when  the  mine 
was  cooled  with  water ;  and  at  last,  at  the  close  of 


CARBONIC  AGED.  69 

the  month,  the  mine  was  ready  for  labor  to  be  re- 
sumed. 

Absorption  of  C02  ~by  Liquids. — Water  dissolves 
its  own  volume  of  CO2  under  the  ordinary  pressure 
of  the  atmosphere;  but  with  increased  pressure,  it 
will  absorb  a  much  greater  amount.  "  Soda  water" 
is  improperly  named,  as  it  contains  no  soda,  but  is 
simply  water  saturated  with  CO2  in  a  copper  receiver 
strong  enough  to  resist  the  pressure  of  10  or  12  at- 
mospheres. This  gas  gives  the  HO  a  pleasant,  pun- 
gent, and  slightly  acid  taste,  and  by  its  escape,  when 
exposed  to  the  air,  produces  a  brisk  effervescence. 
In  beer,  ginger-pop,  cider,  wine,  etc.,  the  CO2  is  pro- 
duced by  the  fermentation  going  on  within.  The  gas 
escapes  rapidly  through  cider  and  wine,  and  so  pro- 
duces only  a  sparkling ;  while  in  a  thick,  viscid  liquid, 
like  beer,  the  bubbles  are  partly  confined,  and  so 
cause  it  to  foam  and  froth.  In  canned  fruits,  catsup, 
etc.,  the  souring  of  the  vegetables  produces  CO2, 
which  sometimes  di  ives  out  the  cork  or  bursts  the 
bottles  with  a  loud  report,  scattering  the  contents 
far  and  wide. 

Liquid  CO-2. — By  a  pressure  of  40  atmospheres,  at  a 
temperature  of  32°,  CO2  becomes  a  colorless  liquid, 
very  much  like  water.  When  this  liquid  is  brought 
out  into  the  air,  it  evaporates  so  rapidly  that  a  por- 
tion is  frozen  into  a  snowy  solid  which  burns  the 
flesh  like  a  red-hot  iron.  By  means  of  liquid  CO2, 
which  has  a  temperature  of  —  150°  F.,  mercury  can  be 
frozen  even  in  a  red-hot  crucible.  Mixed  with  ether, 


68  ELEMENTARY  CHEMISTRY. 

he  is  ready  to  pick  up  his  bone  and  enjoy  the  reward 
of  his  scientific  experiment.  The  celebrated  Upas 
tree  of  Java  seems  not  to  be  altogether  fabulous. 
The  poison  is  not  derived  from  the  tree  itself ;  but 
is  due  to  the  fact  that  it  is  located  in  a  deep  valley 
about  a  half-mile  in  circumference,  in  which  CO2  is 
evolved  in  quantities  sufficient  to  contaminate  the 
entire  atmosphere.  The  valley  is  said  to  be  strewn 
with  the  bones  of  animals  and  birds  which  have 
strayed  into  this  gaseous  lake. 

(702  in  Mines. — Miners  call  C02  choke-damp.  It 
is  produced  by  the  explosion  of  fire-damp  (light  car- 
buretted  hydrogen)  which  accumulates  in  deep  mines, 
and  burns  with  a  shock  like  gunpowder,  forming  dense 
volumes  of  CO2,  which  instantly  destroys  the  lives  of 
all  who  may  have  escaped  the  flames  of  the  explosion. 
Where  CO2  alone  is  found,  it  is  not  considered  as  dan- 
gerous as  the  fire-damp,  since  it  will  not  burn,  and  it 
is  said  that  miners  will  even  venture  "  where  the  air  is 
so  foul  that  the  candles  go  out,  and  are  then  relighted 
from  the  flame  on  the  wick  by  swinging  them  quickly 
through  the  air,  when  they  burn  a  little  while  and 
then  go  out,  and  are  relighted  in  the  same  way." 
CO2  has  been  used  for  the  purpose  of  extinguishing 
fires  in  coal-mines.  In  one  case  an  English  mine 
had  burned  for  20  years,  consuming  a  seam  of  coal 
over  a  space  of  26  acres,  defying  all  attempts  to 
quench  it.  8,000,000  cubic  feet  of  CO2  were  poured 
into  it  day  and  night  for  three  weeks,  when  the  mine 
was  cooled  with  water ;  and  at  last,  at  the  close  of 


CARBONIC  ACID.  69 

the  month,  the  mine  was  ready  for  labor  to  be  re- 
sumed. 

Absorption  of  C02  by  Liquids. — Water  dissolves 
its  own  volume  of  CO2  under  the  ordinary  pressure 
of  the  atmosphere;  but  with  increased  pressure,  it 
will  absorb  a  much  greater  amount.  "  Soda  water" 
is  improperly  named,  as  it  contains  no  soda,  but  is 
simply  water  saturated  with  CO2  in  a  copper  receiver 
strong  enough  to  resist  the  pressure  of  10  or  12  at- 
mospheres. This  gas  gives  the  HO  a  pleasant,  pun- 
gent, and  slightly  acid  taste,  and  by  its  escape,  when 
exposed  to  the  air,  produces  a  brisk  effervescence. 
In  beer,  ginger-pop,  cider,  wine,  etc.,  the  CO2  is  pro- 
duced by  the  fermentation  going  on  within.  The  gas 
escapes  rapidly  through  cider  and  wine,  and  so  pro- 
duces only  a  sparkling ;  while  in  a  thick,  viscid  liquid, 
like  beer,  the  bubbles  are  partly  confined,  and  so 
cause  it  to  foam  and  froth.  In  canned  fruits,  catsup, 
etc.,  the  souring  of  the  vegetables  produces  CO2, 
which  sometimes  diives  out  the  cork  or  bursts  the 
bottles  with  a  loud  report,  scattering  the  contents 
far  and  wide. 

Liquid  CO i. — By  a  pressure  of  40  atmospheres,  at  a 
temperature  of  32°,  CO2  becomes  a  colorless  liquid, 
very  much  like  water.  When  this  liquid  is  brought 
out  into  the  air,  it  evaporates  so  rapidly  that  a  por- 
tion is  frozen  into  a  snowy  solid  which  burns  the 
flesh  like  a  red-hot  iron.  By  means  oi  liquid  CO2, 
which  has  a  temperature  of  —  150°  F.,  mercury  can'be 
frozen  even  in  a  red-hot  crucible.  Mixed  with  ether, 


70  ELEMENTARY  CHEMISTRY. 

and  evaporated  under  the  exhausted  receiver  of  an 
air-pump,  Professor  Faraday  obtained  a  cold  of  166° 
below  zero. 

Ventilation. — The  relation  of  carbonic  acid  to  life 
is  most  important,  and  cannot  be  too  often  dwelt 
upon.  We  exhale  constantly  this  poisonous  gas, 
each  person  contaminating  at  least  10  cubic  feet  of  air 
per  minute.  If  means  are  not  provided  to  furnish 
us  fresh  air  constantly,  we  are  compelled  to  re-breathe 
that  which  our  lungs  have  just  expelled.  The  lan- 
guor, the  sleepiness  we  feel  in  a  crowded  assembly, 
is  the  natural  effect  of  this  narcotic  poison.  The 
idea  of  drinking  in  at  every  breath  the  exhalations 
that  load  the  atmosphere  of  a  crowded,  promiscuous 
assembly,  is  disgusting  as  it  is  noxious.  We  shun 
impurity  in  every  form;  we  dislike  to  wear  the 
clothes  of  another,  or  to  eat  from  the  same  dish; 
we  shrink  from  contact  with  the  filthy,  and  yet  sit- 
ting in  the  same  room  inhale  their  poisonous  breath. 
Health  and  cleanliness  alike  require  that  we  should 
carefully  ventilate  all  public  buildings,  our  school- 
rooms, and  our  sleeping-apartments.  Fresh  air  and 
good  water  are  the  cheapest  luxuries  of  life,  and 
alas !  too  commonly  the  rarest. 

Singular  Truth. — It  is  a  fact,  as  poetical  as  it  is 
characteristic,  that  when  the  CO2  comes  forth  from 
the  lungs  it  is  poisonous,  fully  charged  with  the  seeds 
of  disease,  so  that  if  we  should  re-breathe  it,  death 
would  inevitably  ensue  ;  yet  as  it  passes  out  it  pro- 
duces all  the  tones  of  the  human  voice,  all  songs,  and 


CARBONIC  ACID.  71 

prayers,  and  social  conversation.  Thus  the  gross 
and  deadly  is  by  a  divine  simplicity  made  refined 
and  spiritual,  and  caused  to  minister  to  our  highest 
happiness  and  welfare. 

CARBONIC  OxYD.(CO). — This  is  a  colorless,  almost 
odorless  gas.  It  burns  with  a '  pale,  blue  flame,  ab- 
sorbing an  atom  of  O  from  the  air,  and  becoming 
CO2.  It  is  seen  thus  burning  in  our  coal-stoves,  and 
at  the  top  of  tall  furnace-chimneys.  It  is  caused  by 
an  insufficient  supply  of  O.  It  is  a  deadly  poison, 
and  escaping  from  coal-fires  in  a  close  room  has  often 
produced  death.  The  offensive  odor  which  conies 
out  on  opening  the  door  of  our  coal-stoves  is  caused 
by  the  compounds  of  sulphur  mixed  with  the  CO. 

LIGHT  CARBURETTED  HYDROGEN  (C2H4). — This  is 
the  gas  we  have  already  spoken  of  under  CO2,  as  the 
dreaded  fire-damp  of  miners.  It  is  colorless,  taste- 
less, odorless,  and  burns  with  a  yellowish  flame.  It  is 
formed  in  swamps  and 
low  marshy  places  by 
the  decomposition  of 
vegetable  matter,  and 
on  stirring  the  mud  be- 
neath, will  be  seen  bub- 
bling up  through  the 
wrater.  It  rises  from  Marsh-gas. 

the  earth  in  great  quantities  at  many  places.  At 
Fredonia,  N.  Y.,  it  is  collected  and  used  in  lighting 
the  village.  At  Kanawha,  Va.,  it  is  employed  as  fuel 
for  evaporating  the  brine  in  the  manufacture  of  salt. 


72  ELEMENTARY  CHEMISTRY. 

In  the  oil-wells  of  Pennsylvania,  it  frequently  bursts 
forth  with  explosive  violence,  throwing  the  oil  high 
into  the  air. 

HEAVY  CARBURETTED  HYDROGEN  (C4H4). — Olefiant 
Gas. — This  is  a  colorless  gas,  with  a  sweet,  pleasant 
odor,  and  burns  with  a  clear  white  light. 

ILLUMINATING  GAS  consists  principally  of  the  two 
gases  just  named.  The  proportion  of  the  latter,  or 
olefiant  gas,  which  gives  the  clearness  and  whiteness 
to  the  flame,  determines  its  value.  It  is  made  by 
heating  bituminous  coal  in  large  iron  retorts  until 
coke  only  is  left,  and  all  the  volatile  constituents  are 
driven  off.*  These  are  very  numerous.  Among 
them  are  coal-tar,  ammonia,  carbonic  acid,  carbonic 
oxyd,  nitrogen,  compounds  of  sulphur,  light  and 
heavy  carburetted  hydrogen.  This  mixture  is  first 
cooled  in  the  condenser,  which  is  a  series  of  iron 
tubes  surrounded  by  cold  water,  in  which  the  coal- 
tar  is  deposited,  with  the  ammoniacal  liquids.  Then 
it  is  sprinkled  with  a  spray  of  water,  which  takes  out 
all  the  ammonia,  and  last  of  all  passed  through  milk 
of  lime,  which  absorbs  the  carbonic  acid.  The  re- 
maining gases  form  the  mixture  we  call  "  gas."  This 
is  then  collected  in  the  gasometer,  the  weight  of  which 
forces  it  through  all  the  little  gas-pipes,  and  up  to 
every  jet  in  the  city.  Its  unpleasant  odor,  and  the 
danger  resulting  from  its  escape  in  our  rooms,  are 
the  same  we  have  just  mentioned  in  coal  fires. 

CYANOGEN  (Cy, — NC2). — If  we  mix  hides,  horns,  etc., 

*  A  ton  of  Cannel  coal  will  yield  15,000  feet  of  gas. 


COMBUSTION.  73 

with  carbonate  of  potash  and  iron  filings,  and  heat 
them  in  a  close  vessel,  the  N  and  C  of  these  animal 
substances  in  their  nascent  state  will  combine,  form- 
ing cyanogen.  This  unites  with  the  iron  and  potas- 
sium, forming  the  beautiful  yellow  crystals  of  ferro- 
cyanide  of  potassium,  or  so-called  yellow  prussiate 
of  potash.  The  compounds  of  cyanogen  are  named 
cyanides,  and  are  all  made  from  this  salt. 

HYDROCYANIC  ACID  (HCy). — Prussic  acid,  as  it 
is  commonly  called,  is  a  most  fearful  poison.  A 
single  drop  on  the  tongue  of  a  large  dog  is  said  to 
produce  instant  death.  Ammonia,  cautiously  inhaled, 
is  its  antidote.  Its  bitter  flavor  is  detected  in  peach 
blossoms,  the  kernels  of  plums  or  peaches,  bitter 
almonds,  and  the  leaves  of  wild  cherry. 

FULMINIC  ACID. — This  compound  of  Cy  is  known 
only  as  combined  with  the  various  metals  forming 
fulminates,  which  are  fearfully  explosive.  (The 
term  fulminate  is  from  the  Latin  fulmen,  a  thun- 
derbolt.) Fulminating  mercury  was  used  to  fill  the 
bombs  with  which  the  life  of  Napoleon  III.  was 
attempted  in  1858.  It  is  employed  in  making  gun- 
caps.  A  drop  of  gum  is  first  put  in  the  bottom  of 
the  cap,  over  which  is  sprinkled  a  little  fulminating 
mercury,  and  this  is  sometimes  covered  with  varnish 
to  protect  it  from  the  moisture. 

COMBUSTION. 

Combustion,  in  its  popular  sense,  is  the  union  of  a 
substance  with  O,  and  includes  all  the  various  forms 

4 


74  ELEMENTAEY  CHEMISTRY. 

of  oxydation  we  named  when  treating  of  that  gas. 
The  amount  of  heat  depends  upon  the  quantity  of  O 
which  enters  into  combination. 

Example :  HO  =  9.  Hence,  in  9  Ibs.  of  HO  there 
are  8  Ibs.  of  O,  and  1  Ib.  of  H.  On  the  other  hand, 
CO2  =  22.  Hence,  in  22  Ibs.  of  carbonic  acid  there 
are  6  Ibs.  of  C  and  16  of  O ;  lib.  of  C  unites  with 
2|  Ibs.  of  O.  Therefore,  H  combines  with  three 
times  as  much  O  as  C  does,  and  so  gives  off  three 
times  as  much  heat.  The  intensity  of  the  heat  de- 
pends upon  the  rapidity  with  which  the  fuel  unites 
with  O.  So  we  open  the  draft,  or  blow  a  fire,  to  fur- 
nish this  active  element  of  the  air  in  greater  abun- 
dance. 

The  Igniting  Point. — Although  O  unites  at  all 
temperatures,  yet  combustion,  in  its  popular  sense, 
does  not  commence  until  the  heat  of  the  combustible 
is  raised  to  a  certain  point,  when  we  say  "  it  has 
caught  fire."  The  burning  point  of  any  substance 
is  the  temperature  at  which  it  bursts  into  quick  com- 
bustion. We  elevate  the  heat  of  a  small  portion  to 
the  point  of  rapid  union  with  O,  and  that  part  in 
burning  will  give  off  heat  enough  to  support  the 
combustion  of  the  rest.  Example  :  In  making  a  fire, 
we  take  a  substance  for  kindling  which  unites  with 
O  at  a  low  temperature,  as  paper  or  shavings,  with 
which  we  obtain  heat  enough  to  start  the  combustion 
of  something  that  requires  a  higher  temperature,  as 
chips  or  pine  sticks,  and  thus  gradually  increase  the 
degree  of  heat  until  we  reach  the  igniting  point  of 


COMBUSTION.  75 

coal  or  wood.  If  we  pour  on  much  coal  when  the 
fire  is  low,  we  will  put  it  out,  because  the  fresh  fuel 
lowers  the  heat  below  the  point  of  union  with  O, 
which  is  about  1000°. 

CHEMISTBY  OF  A  FIBE. — All  our  fuel  and  lights,  such 
as  wood,  coal,  oil,  tallow,  etc.,  consist  mainly  of  C 
and  H,  and  are,  therefore,  called  hydrocarbons.  In 
burning,  they  unite  with  the  O  of  the  air,  forming 
HO  and  CO2.  These  both  pass  off,  the  one  as  a  vapor, 
the  other  as  a  gas.  In  a  long  stove-pipe,  the  HO  is 
sometimes  condensed,  and  drips  down,  bringing  soot 
upon  our  carpets.  Ashes  comprise  the  mineral 
matter  contained  in  the  fuel,  united  with  some  of 
the  CO2  produced  in  the  fire.  When  we  first  put 
fuel  in  the  stove,  the  H  is  liberated  with  some  C,  in 
the  form  of  carburetted  hydrogen  gas.  This  burns 
with  a  flame.  Then,  the  volatile  H  having  passed 
off,  we  have  left  the  C,  which  burns  as  a  coal  merely. 
In  maple  there  is  much  more  C  than  in  pine,  so  it 
forms  a  good  "  bed  of  coals."  In  the  burning  of 
fuel  there  is  no  annihilation ;  but  the  HO,  CO2,  and 
the  ashes,  weigh  as  much  as  the  wood  and  the  O 
that  combined  with  it.  No  matter  how  rapidly  the 
fire  burns,  in  the  blaze  of  the  fiercest  conflagration, 
the  elements  unite  in  exact  chemical  equivalents. 
Carbon  is  most  wisely  fitted  for  fuel,  since  the  pro- 
duct of  its  combustion  is  a  gas.  Were  it  not  so,  our 
fires  would  be  choked,  and  before  each  supply  of 
fresh  fuel  we  would  be  compelled  to  remove  the 
ashes  that  filled  the  stove.  In  the  case  of  a 


76  ELEMENTARY  CHEMISTEY. 

candle  it  would  be  still  more  annoying,  as  the  solid 
product  would  fall  around  our  rooms  in  an  acid 
shower  that  would  corrode  every  thing  it  touched. 
Still  another  property  is  the  infusibility  of  carbon. 
Did  it  melt  like  zinc  or  lead  on  the  application  of 
heat,  how  quickly  in  a  hot  fire  would  the  coal  and 
wood  melt,  and  run  down  through  the  grate  and  out 
upon  the  floor  in  a  liquid  mass !  These  properties, 
together  with  its  abundance,  exactly  adapt  it  to 
our  use. 

CHEMISTRY  OF  A  CANDLE. — Flame  is  burning  gas. 
A  candle  is  a  small  "  gas-works,"  and  its  flame  is  the 
same  as  that  of  a  "  gas-burner."  First  we  have  a 
little  cupful  of  tallow  melted  by  the  heat 
of  the  fire  above.  The  ascending  currents 
of  cool  air  which  supply  the  light  with  O 
also  keep  the  sides  of  the  cup  hard,  unless 
the  wind  blows  the  flame  downward,  when 
the  banks  break,  there  is  a  crevasse,  and 
our  candle  runs  down.  Next,  the  melted 
tallow  is  carried  by  capillary  attraction  up 
the  small  tubes  of  the  wick  into  the  flame. 
There  it  is  turned  into  gas  by  the  heat. 
Flame  is  always  hollow,  and  at  the  centre, 

Form  of  flame.  .,  •    i       •       j  i  •        i    <•  n          T  <• 

near  the  wick,  is  the  gas  just  formed.  If  a 
match  be  placed  across  a  flame,  it  will  burn  off  at 
each  side  in  the  ring  of  the  flame,  while  the  centre 
will  be  unblackened.  The  gas  may  be  conducted  out 
of  the  flame  by  a  small  pipe,  and  burned  at  a  little 
distance  from  the  candle.  The  flame  is  hollow 


COMBUSTION.  77 

because  there  is  no  O  at  the  centre.  The  gas  floats 
outward  from  the  wick.  It  comes  in  contact  with 
the  O  of  the  air,  and  the  H,  requiring  least  heat  to 
unite,  burns  first,  forming  HO.  This 
produces  heat  enough  to  make  the 
tiny  particles  of  C,  floating  around  in 
the  flame  of  burning  H,  white-hot. 
They  each  send  out  a  delicate  wave 
of  light,  and  passing  on  to  the  outer 
part,  where  there  is  more  O,  burn, 
forming  CO2.  The  flame  is  blue  at 
the  bottom,  because  there  is  so  much 
O  at  that  point  that  the  H  and  C  burn 
together,  and  so  give  little  light.  The 
HO  may  be  condensed  on  any  cold  sur- 
face. The  CO2  may  be  tested  by  passing  the  invisible 
smoke  of  a  candle  through  lime-water.  The  wick  of 
a  candle  does  not  burn  because  of  the  lack  of  O  at 
the  centre.  It,  however,  is  charred,  as  all  the  volatile 
gas  is  driven  off  by  the  heat.  If  a  portion  falls  over  to 
the  outer  part,  where  there  is  O,  it  burns  as  a  coal. 
If  we  blow  out  a  candle  quickly,  we  can  see  the  gas 
passing  off,  and  can  relight  the  candle  with  an  ignited 
match  held  at  some  distance  from  the  wick.  The 
tapering  form  of  the  flame  is  due  to  the  currents  of 
air  that  sweep  up  from  all  sides  toward  it.  The 
candle  must  be  snuffed,  because  the  long  wick  would 
cool  the  blaze  below  the  igniting  point  of  C  and  O, 
and  the  C  would  pass  off  unconsumed.  A  draught 
of  air,  or  any  cold  substance  thrust  into  the  flame, 


Match  in  flame. 


78 


ELEMENTAEY   CHEMISTKY. 


Water  In  a  flame. 


produces  the  same  result,  and  deposits  the  C  as 
soot.  Plaited  wicks  are  sometimes  used,  which, 
being  thin,  fall  over  to  the  outside  and  burn,  requir- 
ing no  snuffing. 

CHEMISTRY  OF  A  LAMP. — A  chimney  confines  the 
hot  air  and  makes  a  draught  of  O  through  the  flame. 
A  flat  wick  is  used,  as  it  pre- 
sents more  surface  to  the  ac- 
tion of  the  O.  Argand  lamps 
are  made  with  a  hollow  wick, 
so  as  to  admit  O  into  the  centre 
of  the  blaze.  The  film  which 
gathers  on  a  chimney  when  we 
first  light  a  lamp,  is  the  HO 
produced  in  the  flame,  con- 
densed on  the  cold  glass.  A  pint  of  oil  forms  a  full 
pint  of  HO.  Spirits  of  turpentine,  tar,  pine-wood, 
etc.,  contain  an  excess  of  C,  and 
not  enough  H  to  heat  it  to  the 
point  of  union  with  O.  These, 
therefore,  produce  clouds  of  soot. 
Alcohol  contains  an  excess  of  H 
and  little  C,  hence  it  gives  off 
great  heat  and  but  little  light. 
Davy's  Safety  Lamp,  used  by 
miners,  consists  of  an  ordinary 
oil-lamp,  surrounded  by  a  cylin- 
der of  fine  wire-gauze.  Even  if 
the  flame  of  the  lamp  is  thrown 
against  the  outside,  or  inflam- 


COMBUSTION.  79 

mable  gases  from  the  mine  come  into  the  inside,  the 
wire  conducts  off  the  heat,  and  reduces  it  below  the 
point  of  union  with  O,  so  no  flame  can  pass  through, 
and  no  gas  on  the  outside  ignite. 
Through  carelessness  fearful  acci- 
dents have  occurred,  even  since  this 
lamp  has  been  used.  Miners  become 
extremely  negligent,  and  an  account 
is  given  of  an  explosion,  in  which 

.  1in  i-iiT       Wire-gauze  in  flame. 

about  a  hundred  persons  were  killed, 

caused  by  a  lamp  being  hung  on  a  nail  by  a  hole 

broken  through  the  wire-gauze. 

EXTINGUISHING  FIRES. — Blowing  on  a  candle  or 
lamp  extinguishes  it,  because  it  lowers  the  heat  of 
the  flame  below  the  point  of  union  of  C  with  O. 
Fires  are  put  out  by  HO  partly  for  the  same  reason, 
and  also  because  it  envelops  the  wood  and  shuts  off 
the  air.  If  a  person's  clothes  take  fire,  the  best  pos- 
sible remedy  is  to  wrap  him  in  a  blanket,  carpet, 
coat,  or  even  in  his  own  garments.  This  smothers 
the  fire,  by  shutting  out  the  O  of  the  air.  Great 
care  should  be  taken  in  a  fire  not  to  open  the  doors 
or  windows,  so  as  to  cause  a  draught  of  air.  The 
entire  building  may  burst  into  a  blaze,  when  the  fire 
might  have  been  confined  for  want  of  O,  and  so 
easily  extinguished. 

SPONTANEOUS  COMBUSTION. —  Sometimes  chemical 
changes  take  place  in  combustible  •  substances, 
whereby  heat  enough  is  generated  to  cause  ignition. 
Lime  occasionally  absorbs  HO,  so  as  to  set  fire  to 


80  ELEMENTARY  CHEMISTBY. 

wood  in  contact  with  it.  Fresh-burned  charcoal 
has  the  power  of  absorbing  gases  in  its  pores  so 
vigorously  as  to  become  ignited.  Heaps  of  coal 
often  take  fire  from  the  iron  pyrites  contained  in 
them  being  decomposed  by  the  moisture  of  the  air. 
The  waste  cotton  used  in  mills  for  wiping  oil  from 
the  machinery,  is  thrown  into  large  heaps,  and  ab- 
sorbs O  from  the  air  so  rapidly  that  it  often  bursts 
into  a  blaze.  Instances  have  been  given  of  the  hu- 
man body  itself  taking  fire  spontaneously.  Jt  hap- 
pens most  generally  in  the  case  of  intemperate 
persons.  In  these  instances  the  fire  was  not  easily 
subdued  nor  communicated  to  other  substances,— 
the  body  having  even  burned  to  ashes  while  the 
garments  were  unconsumed. 

OX-HYDBOGEN  BLOW-PIPE.*  —  In  the  Compound 
Blow-pipe  a  jet  of  O  is  introduced  into  the  centre 
of  a  jet  of  burning  H,  producing  a  solid  flame. 

Inasmuch  also  as  H  unites 
with  so  much  O,  an  im- 
mense heat  is  developed. 
A  watch-spring  will  burn 
in  it  with  a  shower  of 
sparks.  Platinum,  the 
most  infusible  of  metals, 

requiring  a  temperature  of  4591°,  or  over  twenty 
times  that  of  boiling  water,  readily  melts.  In  the 
common  hollow  flame,  as  we  have  seen,  the  little 

*  See  Frontispiece. 


COMBUSTION.  81 

particles  of  solid  C,  heated  by  the 
burning  H,  produce  the  light.  As 
there  is  no  solid  body  in  the  Blow- 
pipe flame,  it  is  scarcely  luminous. 
If,  however,  we  insert  in  it  a  bit  of 
lime,  a  most  dazzling  light  is  pro- 
duced. This  is  called  the  "  Drum- 
mond,"  "Lime,"  or  "Calcium" 
Light,  and  has  been  seen  at  a  dis- 
tance of  one  hundred  and  eight 
miles  in  broad  sunlight. 

Mow-pipe. — In  the  common  blow- 
pipe, used  by  jewellers,  a  current 
of  O  from  the  lungs  is  thrown  into 
the  centre  of  an  alcohol  blaze.  It 
is  thus  rendered  solid  and  its  heat  cr°mmon 
greatly  increased.  Near  the  extreme  point  of  the 
flame  the  unconsumed  gases  are  very  hot,  and  com- 
bine readily  with  the 
O  of  any  substance  in- 
serted into  the  flame 
at  that  part,  which  is 
therefore,  called  the 
"  reducing  flame."  Just 

Reducing  liame. 

at    the    point    of    the 

flame,  the  O  thrown  from  the  lungs  is  highly  heated, 
and  is  ready  to  combine  with  any  substance,  and  is 
therefore  called  the  "  Oxydizing  flame"  Example : 
Hold  a  copper  cent  in  the  flame  of  an  alcohol  lamp. 

4* 


82  ELEMENTARY  CHEMISTRY. 

In  the  "  reducing  flame"  its  rust  or  oxyd  of  copper  will 
be  all  cleaned  off,  and  the  cent  will  shine  as  brightly 

as  if  just  from  the  mint. 
In  the  "  oxydizing  flame" 
the  various  oxyds  of  cop- 
per will  be  formed  over  the 
surface,  and  so  the  most 
_  ,.  .  _  beautiful  play  of  colors 

Oxydizm-  flame.  r     J 

will  flash  from  side  to  side 
as  we  move  the  cent  from  one  part  to  the  other. 

THE  ATMOSPHERE. 

The  "  air  we  breathe"  consists  of  N,  O,  CO2,  and 
watery  vapor.  The  first  composes!,  the  second-^, 
the  third  yoV^  an^  *he  ^as^  a  variable  proportion. 
The  N  and  O  form  so  large  a  part,  that  they  are  con- 
sidered in  ordinary  calculation  to  compose  the  whole 
atmosphere.  A  very  clear  idea  of  the  proportion  of 
these  several  constituents  may  be  formed  by  conceiv- 
ing the  air,  not  as  now  dense  near  the  surface  of  the 
earth,  and  gradually  becoming  rarified  as  we  ascend 
to  is  extreme  limit  of  50  miles,  but  of  a  density 
throughout  equal  to  that  which  it  now  possesses  near 
the  earth.  The  atmosphere  would  then  be  but  about 
five  miles  high.  The  vapor  would  form  a  sheet  of 
HO  over  the  ground  five  inches  deep,  next  the  CO2 
a  layer  of  13  feet,  then  the  N  a  layer  of  one  mile,  and 
last  of  all,  the  O  a  layer  of  four  miles.  ( Graham.)  In 
this  arrangement  we  have  supposed  the  gases  to  be 
placed  in  the  order  of  their  specific  gravity.  The 


THE  ATMOSPHERE.  83 

atmosphere  is  not  thus  composed  in  fact,  the  various 
gases  being  equally  mingled  throughout,  in  accord- 
ance with  a  principle  called  the  "  Law  of  the  Diffu- 
sion of  Gases."  If  we  throw  a  piece  of  lead  into  a 
brook,  it  will  settle  instantly  to  the  bottom  by  the 
law  of  gravitation,  and  remain  there  forever  by  the 
law  of  inertia.  But  if  we  throw  out  into  the  atmos- 
phere a  quantity  of  CO2,  it  sinks  for  an  instant,  then 
immediately  begins  to  mingle  with  the  surrounding 
air,  and  is  soon  entirely  dissipated.  Example :  If  we 
invert  an  open-mouthed  bottle  full  of  H  over  another 
full  of  CO2,  in  a  few  hours  the  H,  light  as  it  is,  will 
have  crawled  down  into  the  lower  jar ;  and  the  CO2, 
heavy  as  it  is,  will  have  crawled  up  into  the  upper 
jar ;  and  the  gases  will  be  found  equally  mixed.  By 
this  law  the  proportion  of  the  elements  of  the  at- 
mosphere is  the  same  everywhere,  and  has  not  varied 
within  historic  times.  Samples  have  been  analyzed 
from  every  conceivable  place,  from  polar  and  torrid 
regions,  from  prairies  and  mountain-tops,  from  bal- 
loons and  mines,  and  even  from  bottles-full  sealed 
up  in  the  ruins  of  Herculaneum,  and  the  result  is 
the  same.  These  gases  do  not  form  a  chemical 
compound,  but  a  mere  mechanical  mixture,  and 
they  are  as  distinct  in  the  air  as  so  many  grains  of 
wheat  and  corn  mingled  in  a  measure.  Each  of  these 
has  its  separate  use  and  mission.  The  action  of  O 
and  N  we  have  already  seen. 

Uses  of  CO-2. — This  bears  the   same  relation   to 
vegetable  that  0  does  to  animal  life.     The  leaf-*-the 


84  ELEMENTABY  CHEMISTRY. 

plant-lungs — through  its  million  of  little  stommata, 
or  mouths,  drinks  in  the  CO2.  In  that  minute  leaf- 
laboratory,  by  the  action  of  the  sunbeam,  the  CO2 
is  decomposed,  the  C  being  applied  to  build  up  the 
plant,  and  the  O  returned  to  the  air  for  our  use. 
Plants  breathe  out  O  as  we  breathe  out  CO2.  We 
furnish  vegetables  with  air  for  their  use,  and  they  in 
turn  supply  us.  There  is  thus  a  mutual  dependence 
between  the  animal  and  the  vegetable  world.  Each 
relies  upon  the  other.  Deprived  of  plants  we  would 
soon  exhaust  the  O  from  the  air,  supply  its  place 
with  CO2,  and  die;  while  they,  removed  from  us, 
would  soon  exhaust  the  CO2,  and  die  as  certainly. 
"We  poison  the  air  while  they  purify  it.  Each  tiny 
leaf  and  spire  of  grass  is  thus  imbibing  our  foul 
breath,  and  returning  it  to  us  pure  and  fresh.*  This 
interchange  of  office  is  so  exactly  balanced,  that,  as 
we  have  seen,  the  proportion  of  CO2  and  of  O  never 
varies.  "  Two  hundred  million  tons  of  coal  are  now 
annually  burned,  producing  six  hundred  million  tons 

*  In  connection  with  this  subject  it  is  well  to  notice  that  the 
current  idea,  that  plants  exhale  CO2  at  night,  is  now  known 
to  be  erroneous.  They  purify  the  air  while  the  sunlight  shines 
upon  them,  and  hi  darkness  are  at  rest.  Plants  in  a  room  are, 
therefore,  healthy,  unless  they  are  of  such  varieties  as  emit  a 
poisonous  odor.  Certainly  the  freshness  and  cheeriness  given  to 
an  apartment  by  a  stand  of  flowers,  or  even  a  few  pots  in  a  win- 
dow-bench, must  delight  all ;  while  the  refining  influence  of  the 
beautiful  in  nature  would  suggest  the  propriety  of  adorning  our 
dwellings  in  this  simple  manner,  did  not  chemistry  teach  its  prac- 
tical utility  as  a  mode  of  purifying  the  air. 


THE  ATMOSPHERE.  85 

of  CO2.  A  century  ago,  hardly  a  fraction  of  that 
amount  was  burned,  yet  this  enormous  aggregate  has 
not  changed  the  proportion  in  the  least."  ( Youmans.) 

Use  of  Watery  Vapor. — We  have  already  seen  the 
uses  of  HO.  As  vapor,  it  is  everywhere  present  and 
ready  to  supply  the  wants  of  animals  and  plants. 
Were  the  air  dry,  our  flesh  would  shrivel  into  that 
of  a  mummy,  and  leaves  would  wither  as  they  do  in 
an  African  simoom.  Hivers  and  streams  flow  to  the 
ocean  ;  yet  all  their  fountains  are  fed  by  the  currents 
that  move  in  the  air  above  us.  HO  rises  in  the  air 
as  vapor,  flows  on  to  colder  regions,  falls  as  rain, 
dew,  snow,  or  hail,  and  then  working  as  it  goes  what- 
ever it  finds  to  do,  moistening  a  plant  or  turning  a 
water-wheel,  it  finds  its  way  back  to  the  ocean. 
Thus  Niagara  itself  must  first  have  risen  to  the 
clouds  as  vapor  before  it  can  fall  as  a  cataract. 

PERMANENCE  OF  THE  ATMOSPHERE. — Did  the  ele- 
ments readily  unite  to  form  nitric  acid,  instead  of,  as 
now,  with  great  difficulty,  and  only  in  a  thunder- 
storm, we  would  be  constantly  exposed  to  a  shower 
of  this  corrosive  acid  that  would  be  destructive  to 
all  vegetation,  clothing,  and  even  our  bodies  them- 
selves.— O  and  N  have  never  been  solidified  or  lique- 
fied by  the  severest  cold  or  pressure,  while  CO2  re- 
quires a  force  that  is  never  reached  in  nature. 
Watery  vapor,  on  the  contrary,  is  deposited  as  dew 
or  rain  by  a  slight  change  of  temperature ;  this  is 
necessary  to  supply  the  wants  of  vegetation  and  life. 
But  were  the  same  true  of  the  other  constituents, 


86  ELEMENTARY  CHEMISTEY. 

they  would  come  raining  down  upon  us  in  most  dis- 
astrous showers;  and  in  winter  we  would  be  com- 
pelled to  melt  what  air  we  should  need,  and  carry  a 
supply  with  us  constantly.  Life  itself  would  be  un- 
endurable under  such  circumstances.  Again,  the 
permanence  of  the  air  produces  all  the  uniformity 
of  sound.  Were  the  proportions  of  the  atmosphere 
to  change,  all  "familiar  voices"  would  become  strange 
and  uncouth  to  us,  while  the  harmonies  of  music 
would  shock  us  with  unwonted  discord.  If,  by  some 
means,  the  air  of  a  concert-room  could  be  changed 
to  H,  for  instance,  the  bass  voices  would  become  ir- 
resistibly comic  and  shrill,  while  the  tenor  would 
emulate  railway  whistles.  It  is  pleasant  to  notice 
how  each  element  of  the  air  is  adapted  for  a  special 
work,  and  all  fitted  to  the  present  order  of  nature. 

THE  HALOIDS. 

Chlorine ••••Symb-,  Clj  Equiv-,  35-5;  Spec-  Grav-,    2-47 

Iodine "       1}         "      126-8;  "                2-47 

Bromine-...            Brj      "         -80;  "    (at  30°),  3-18 

Fluorine-.-.     "      Fl  j       "          -19}  "                  1-31 

These  four  elements  are  closely  allied,  and  form  a 
class  of  compounds  known  as  the  haloid  salts,  from 
hals,  salt,  because  they  resemble  common  salt. 

CHLORINE  is  named  from  its  green  color.  It  is 
chiefly  found  in  common  salt,  of  which  it  forms  60 
per  cent.,  and  is  made  by  moderately  heating  it  with 
black  oxyd  of  manganese,  sulphuric  acid,  and  water. 
This  mixture  liberates  the  gas  in  great  quantities. 


CHLORINE. 


87 


It  is  heavier  than  common  air,  and  so  may  be  col- 
lected by  displacement. 


Making  Chlorine. 

Properties.  —  It  has  a  greenish-yellow  color,  and  a 
peculiarly  disagreeable  odor.  It  produces  a  suffo- 
cating cough,  which  can  be  relieved  by  breathing 
ammonia  or  ether.  Arsenic,  antimony,  Dutch  gold- 
leaf,  phosphorus,  etc.,  combine  with  it  so  rapidly  as 
to  inflame  ;  —  powdered  antimony  producing  a  shower 
of  brilliant  sparks  when  slowly  dropped  into  a  jar 
of  Cl.  Cold  water  absorbs  about  twice  its  volume 
of  the  gas,  which  soon  turns  to  hydro- 
chloric acid  (HC1)  in  the  sunlight.  It  has 
such  a  powerful  affinity  for  H,  that  it  will 
even  attract  it  out  of  a  moist  organic  body, 
and  form  HC1.  It  acts  thus  upon  turpen- 
tine, depositing  its  C  in  great  flakes  of  soot. 
It  discharges  the  color  of  indigo,  ink,  wine, 
etc.,  almost  instantaneously.  It  has  no 
effect  on  printers'  ink,  as  that  contains  no  H. 


inC1- 


88 


ELEMENTARY  CHEMISTRY. 


HYDROCHLORIC  ACID  (HC1) — Muriatic  Acid. — When 
Cl  and  H  are  mixed  and  ex- 
posed to  the  direct  sunlight 
they  unite  with  an  explosion. 
In  the  arts,  HC1  is  prepared 
from  sulphuric  acid  and  com- 
mon salt. 

NaCl-hSO3.HO 


Making  HC1. 


NaO  .  S03  +  HC1 


Properties. — It  is  an  irrespirable,  irritating,  acid 
gas,  with  an  intense  attraction  for  HO,  which  causes 
it  to  produce  white  fumes  in  the  air.  Water  absorbs 
480  times  its  bulk,  forming  the  liquid  known  as 
"Muriatic  Acid.'"  It  unites  with  the  metals,  and 
forms  chlorides.  When  pure  it  is  colorless,  but  has 
ordinarily  a  yellow  tinge,  due  to  various  impurities. 
Its  tests  are  ammonia,  with  which  it  forms  a  white 
cloud  of  sal-ammoniac  fumes,  and  nitrate  of  silver, 
from  which  it  precipitates  chloride  of  silver.  With 
NO5  it  forms  aqua-regia,  or  royal  water,  so  named 
because  it  dissolves  gold,  the  "  king  of  the  metals." 
It  sets  free  chlorine,  which,  in  its  nascent  state,  at- 
tacks the  gold  and  combines  with  it. 

CHLORIDE  OF  LIME  (Bleaching  Powder}. — This  is 
prepared  by  passing  a  current  of  Cl  over  pans  of 


CHLORINE.  89 

fresh  slacked  lime.     It  is  much  used  in  bleaching 
and  as  a  disinfectant. 

Bleaching. — In  domestic  bleaching  the  cloth  is  first 
boiled  with  strong  soap,  to  dissolve  all  the  grease 
and  wax,  and  then  laid  upon  the  grass,  being  fre- 
quently wet  to  hasten  the  action  of  the  air  and  sun. 
The  dew  seems  to  have  a  peculiar  influence,  while 
the  corrosive  ozone  of  the  atmosphere  doubtless  aids 
in  the  process.  The  H  of  the  coloring  matter  unites 
with  the  O  of  the  air  or  dew,  forming  HO,  and  thus 
destroying  the  coloring  compound.  This  was  essen- 
tially the  process  long  pursued  in  Holland,  where 
all  linens  were  formerly  carried  for  bleaching  :  hence 
the  term  "  Holland  linen,"  still  in  use.  The  HO 
about  Haarlem  was  thought  to  have  peculiar  prop- 
erties, and  no  other  could  compete  with  it.  Cloths 
sent  there  were  kept  the  entire  summer,  and  were 
returned  in  the  fall.  Later  a  similar  plan  was 
adopted  in  England.  But  the  vast  extent  of  grass- 
land required,  the  time  occupied,  and  the  temptation 
to  theft,  made  the  process  extremely  tedious  and 
expensive.  The  statute  laws  of  that  time  abound  in 
penalties  for  cloth  stealing.  It  is  estimated  that  all 
the  men,  women,  and  children  in  the  world  could 
not,  by  the  old  way,  bleach  all  the  cloth  that  is  now 
used.  At  present  the  cloth  is  well  washed,  and 
boiled  in  water  with  strong  alkalies,  to  remove  the 
grease,  <fec. ;  next  it  is  passed  through  a  solution  of 
chloride  of  lime,  and  lastly  through  diluted  SO3.  In 
this  step  the  SO3  unites  with  the  lime,  and  sets  free 


90  ELEMENTARY  CHEMISTRY. 

the  01,  which  in  turn  combines  with  the  H  of  the 
coloring  matter,  forming  HC1,  and  thus  bleaches 
the  cloth  most  perfectly.  About  twenty-four  hours 
are  required  for  this  process,  and  the  cost  is  not 
quite  a  cent  per  yard.  Paper  rags  are  bleached  in 
the  same  way  in  paper-mills.  Stains  can  be  re- 
moved from  uncolored  cloth  by  a  little  chloride  of 
soda  (Labarraque's  Solution),  which  can  be  obtained 
of  any  druggist.  Place  the  cloth  in  this  liquid,  and 
if  obstinate,  pour  on  a  little  boiling  HO,  or  place  it 
in  the  sun  for  some  hours.  Then  rinse  thoroughly 
in  cold  HO,  and  dry. 

Disinfectant. — Chlorine  is  a  powerful  disinfectant. 
It  breaks  up  the  offensive  substance  by  uniting  with 
its  H,  as  in  bleaching.  Other  disinfectants,  as  burnt 
paper,  sugar,  etc.,  only  disguise  the  ill  odor  by  sub- 
stituting a  stronger  one.  In  the  sick-room  Cl  is  set 
free  from  chloride  of  lime  by  exposing  it  to  the  air 
in  a  saucer  with  a  little  HO.  The  gas  soon  passes 
off,  though  the  process  may  be  hastened  by  adding 
a  few  drops  of  dilute  SO3.  A  handful  of  chloride  of 
lime,  thrown  under  the  floor,  will  vanquish  even  a 
dead  mouse,  or  any  other  odoriferous  domestic  ani- 
mal, living  or  dead. 

BROMINE — named  from  its  bad  odor — is  a  poison- 
ous, volatile,  deep-red  liquid,  with  the  general  prop- 
erties of  01.  It  is  principally  found  in  sea-water, 
and  forms  bromides  with  the  metals,  which  are  used 
in  photography. 

FLUORINE  is  the  only  element  that  will  not  unite 


FLUORINE. — IODINE.  91 

with  O,  and  for  this  reason  exists  in  the  enamel  of 
the  teeth.  It  is  found  in  Derbyshire  or  fluor  spar 
(Ca.Fl),  of  which  beautiful  ornaments  are  made. 
It  unites  with  H,  forming  hydrofluoric  acid  (HF1), 
noted  for  its  corrosive  action  on  glass.  This  eats  out 
the  silica  or  sand  from  the  glass,  and  is  therefore 
used  for  etching  labels  on  glass  bottles  and  names 
on  shop-windows.  'Example  :  Powdered  fluor  spar 
is  placed  in  a  lead  tray,  and  covered  with  dilute 
SO3.  The  heat  of  a  lamp  applied  beneath,  for  a 
moment  only,  liberates  the  gas  in  white  fumes  very 
rapidly.  The  plate  of  glass  is  covered  with  wax, 
and  the  design  to  be  etched  is  traced  upon  it  with 
a  sharp-pointed  instrument.  This  is  then  laid  over 
the  tray,  and  the  escaping  gas  soon  etches  the  lines 
laid  bare  into  an  appearance  like  ground  glass. 
A  solution  of  HF1  in  HO  is  often  sold  for  this  pur- 
pose. It  is  kept  in  lead  or  gutta-percha  bottles, 
combines  Avith  HO  with  a  hissing  sound,  like  red- 
hot  iron,  and  must  be  handled  with  care,  as  a 
minute  drop  even  will  sometimes  produce  an  in- 
curable ulcer. 

IODINE  is  named  from  its  beautiful  violet-colored 
vapor.  It  is  made  from  kelp — the  ashes  of  sea-weed, 
and  is  found  in  sea-water  and  in  some  mineral  springs. 
It  has  a  bluish-black,  metallic  appearance,  and  is 
sparingly  soluble  in  HO,  but  readily  in  ether  or  alco- 
hol. It  inflames  spontaneously  when  in  contact  with 
phosphorus.  Its  compounds  with  .the  metals,  called 
the  iodides,  are  remarkable  for  their  variety  and  bril- 


92  ELEMENTARY  CHEMISTRY. 

liancy  of  color.  It  stains  cloth  a  yellowish  tint,  which 
may  be  removed  by  a  solution  of  iodide  of  potassium. 
Its  test  is  starch,  forming  the  blue  iodide  of  starch. 
It  reveals  the  presence  of  this  substance  in  potatoes, 
apples,  etc.  It  is  much  used  in  medicine  to  scatter 
scrofulous  or  cutaneous  eruptions  and  swellings. 

BORON. 
Symbol,  B  ....  Equivalent,  10.9. 

BORON  is  known  in  nature  only  in  combination  with 
O,  as  boracic  acid  (BO3).  This  is  found  in  the  vol- 
canic districts  of  Tuscany.  Here,  for  an  area  of 
about  30  miles,  is  a  wild,  mountainous  region,  of  ter- 
rible violence  and  confusion.  The  surface  is  ragged 
and  blasted.  Everywhere  there  issue  from  the  ground 
jets  of  steam,  filling  the  air  with  most  offensive 
odors.  The  earth  itself  shakes  beneath  the  feet,  and 
frequently  yields  to  the  tread,  engulfing  man  and 


Preparing  BO3. 

beast.     "  The  waters  below  are  heard  boiling  with 
strange  noises,  and  are  seen  breaking  out  upon  the 


SILICON.  93 

surface.  Of  old,  it  was  regarded  as  the  entrance  to 
hell.  The  peasants  pass  by  in  terror,  counting  then- 
beads  and  imploring  the  protection  of  the  Virgin." 
In  the  midst  of  this  scene  of  horror  a  most  lucrative 
business  has  been  established.  These  jets  of  steam 
are  charged  with  boracic  acid.  A  series  of  basins 
are  excavated  up  the  sides  of  the  principal  moun- 
tain. These  are  filled  with  cold  HO  from  the  neigh- 
boring springs.  Into  these  basins  the  jets  of  steam 
are  conducted.  The  HO  absorbs  the  boracic  acid, 
and  becomes  itself  heated  to  the  boiling-point.  It 
is  then  drawn  off  into  the  next  lower  basin.  This 
process  is  continued  until  the  bottom  one  is  reached, 
when  the  HO  runs  into  leaden  pans  heated  by  the 
steam  from  the  earth ;  here  the  HO  is  evaporated, 
and  the  boracic  acid  is  collected.  3,000,000  Ibs.  are 
sold  per  annum. 

BORAX  is  a  biborate  of  soda  (NaO.2BO3).  It  is  em- 
ployed largely  in  welding.  It  dissolves  the  oxyd  of 
the  metal,  and  keeps  the  surface  bright  for  soldering. 
It  softens  hard  water  by  uniting  with  the  soluble 
salts  of  lime  or  magnesia,  and  making  insoluble  ones 
which  settle  and  form  a  thin  sediment  in  the  bottom 
of  pitchers  in  which  it  is  placed. 

SILICON. 

Symbol,  Si ....  Equivalent,  14. 

Sources. — This  is  commonly  found  in  combination 
with  O,  as  silicic  acid,  silica,  silex  or  quartz  (SiO2). 
It  composes  45  per  cent,  of  the  crust  of  the  earth. 


94  ELEMENTAEY  CHEMISTRY. 

It  forms  beautiful  crystals  and  some  of  the  most  pre- 
cious gems.  When  pure,  it  is  transparent  and  color- 
less, as  in  rock-crystal.  Jasper,  amethyst,  agate, 
chalcedony,  opal,  topaz,  chrysoprase,  sardonyx,  etc., 
are  all  common  flint-stone  or  quartz,  colored  with 
some  metallic  oxyd.  Sand  is  mainly  fine  quartz, 
which,  when  hardened  and  cemented,  we  call  sand- 
stone. Yellow  or  red  sand  is  colored  by  iron-rust. 

Properties.  —It  is  tasteless,  odorless,  and  colorless. 
It  seems  very  strange  to  call  such  an  inert  substance 
an  acid ;  yet  it  is  a  true  acid,  since  it  unites  with  the 
alkalies,  neutralizes  their  properties,  and  forms  a 
large  class  of  salts  known  as  the  silicates,  which 
are  found  in  the  most  common  rocks — Example : 
granite. 

SILICA  IN  SOIL  AND  PLANTS. — Silica  is  insoluble  in 
HO,  unless  it  contains  some  alkali.  When  the  sili- 
cates, so  abundant  in  rocks,  disintegrate  and  form 
soil,  the  alkali  and  silica  are  both  dissolved  in  the 
water,  and  taken  up  by  the  roots  of  plants.  We  see 
the  silica  as  grit  in  maple-sugar,  or  as  deposited  on 
the  surface  of  scouring-rushes  or  sword-grass,  on 
which  we  have  so  often  cut  our  ringers.  It  gives 
stiffness  to  the  stalks  of  wheat  and  other  grains,  and 
produces  the  hard,  shiny  surface  of  bamboo,  corn,  etc. 

PETRIFACTION. — Certain  springs  contain  large  quan- 
tities of  some  alkali-;  their  waters,  therefore,  dissolve 
silica  abundantly.  If  we  place  a  bit  of  wood  in 
them,  as  fast  as  it  decays,  particles  of  silica  will 
take  its  place — atom  by  atom — and  thus  petrify  the 


SULPHUR.  95 

wood.     The  wood  has  not  been  changed  to  stone,  but 
has  been  replaced  by  stone. 

SULPHUR. 

Symbol,  S  ••••  Equivalent,  16  .-••  Specific  Gravity,  2. 

Sources. — Sulphur  is  found  native  in  volcanic  re- 
gions. It  is  mined  at  Mount  .ZEtna  in  great  quanti- 
ties. Combined  with  the  metals  it  forms  sulphurets, 
known  as  cinnabar,  iron  pyrites,  etc.  Combined  with 
SO3  it  exists  in  gypsum  (plaster),  heavy  spar,  and 
other  sulphates.  It  is  found  in  the  hair,  and  many 
dyes  contain  lead  which  unites  with  this  S,  and  forms 
a  black  compound  that  stains  the  hair.  It  is  con- 
tained in  eggs,  and  so  tarnishes  our  spoons  by  form- 
ing a  sulphuret  of  silver.  It  is  always  present  in  the 
flesh,  and  hence  manifests  itself  in  our  perspiration  ; 
with  some  persons  it  is  so  abundant  as  to  produce  a 
disagreeable  odor.  In  commerce  it  is  sold  as  brim- 
stone, formed  by  melting  S  and  running  it  into  moulds ; 
also  as  flowers  of  sulphur,  obtained  by  sublimation. 

Properties. — It  is  insoluble  in  HO,  and  hence 
tasteless,  although  when  taken  in  molasses  it  seems 
otherwise.  Its  solvent  is  bisulphide  of  carbon,  but 
it  will  dissolve  somewhat  in  oil  of  turpentine.  It  is 
a  non-conductor  of  heat,  and  crackles  when  we 
grasp  it  with  a  warm  hand.  It  manifests  itself  un- 
der three  allotropic  forms  :  1st,  octohedron  crystals ; 
2d,  prismatic  crystals ;  3d,  an  amorphous  (without 
form)  or  uncrystallized  state.  The  last  is  the  most 
interesting.  Example :  If  sulphur  be  melted,  and 


96  ELEMENTAEY  CHEMISTRY. 

then  heated  up  to  480°,  it  changes  into  a  thick, 
viscid,  dark-colored  liquid  like  molasses,  which,  if 
poured  into  cold  water,  is  elastic  like  india-rubber. 
In  this  form  it  is  used  for  taking  impressions  of 
medals,  coins,  &c. 

SULPHUROUS  ACID  (SO2),  an  irrespirable,  suffocating 
gas,  is  formed  by  S  burning  in  the  air,  as  in  the 
lighting  of  a  match.  It  is  very  poisonous,  and  ex- 
tinguishes combustion.  If  our  "chimney  burns" 
at  any  time,  we  can  easily  quench  the  flame  by  pour- 
ing a  little  S  into  the  stove.  Its  compounds  are 
called  sulphites. 

Uses. — It  is  used  for  bleaching  silk,  straw,  and 
woollen  fabrics.  Cl  cannot  be  used  for  these  sub- 
stances, as  it  turns  them  yellow,  but  SO2  unites  with 
the  coloring  matter,  and  forms  a  colorless  compound. 
Its  action  is  therefore  very  different  from  that  of 
Cl.  Example  :  A  red  rose,  bleached  in  the  fumes  of 
burning  S,  can  be  restored  to  its  original  color  by 
a  little  very  dilute  SO3.  This  acid  being  stronger, 
neutralizes  the  action  of  the  SO2.  New  flannels, 
washed  in  strong  soap,  turn  yellow,  because  the 
alkali  of  the  soap  unites  with  the  SO2  used  in 
bleaching  the  cloth,  and  thus  sets  free  the  original 
color. 

SULPHURIC  ACID  (SO3)— Oil  of  Vitriol,  the  "King 
of  the  Acids." — This  acid  is  of  the  utmost  impor- 
tance to  the  manufacturer  and  chemist,  as  it  is  used 
in  the  preparation  of  nearly  all  other  kinds,  forming 
many  valuable  compounds.  The  acid  of  the  shops 


SULPHUR. 


97 


is  a  strong  solution  of  the  gas  in  HO.    Its  com- 
pounds are  called  sulphates. 

Preparation.—  Example  :  If  in  a  jar  we  burn  a 
little  S,  it  will  soon  become  filled  with  the  fumes  of 
SO2.  One  atom  of  O  added  to  this  SO2  would  make 
it  S03.  It  will  be  remembered  that  NO5  easily  parts 
with  its  O.  Now  if  we  stir  the  fumes  with  a  swab 
wet  with  NO6,  we  will  notice  that  the  white  gas  in 
the  jar  turns  red,  and  will  recognize  the  old  "  nitrous 
acid  fumes,"  and  on  testing  we  will  find 
SO3  in  the  jar,  especially  if  there  be  any 
HO  at  the  bottom  to  absorb  it.  The  nitric 
acid  has  turned  the  SO2  into  SO3.  This  is 
essentially  the  plan  pursued  in  its  manu- 
facture on  a  large  scale.  AJI  immense 
chamber,  perhaps  three  hundred  feet  in 
length,  is  lined  with  lead  and  intersected 
by  perforated  leaden  partitions  to  mix  the  gases 
more  thoroughly  as  they  pass  through.  In  this  are 


and  ^° 


Manufacture  of  SO8. 


admitted  steam,  fumes  of  burning  sulphur,  and  nitric 
acid,  from  furnaces  at  the  side. 


NO5  +  3  SO2 
Vvx. 

NO2  4-  3  SO3 


The  N05  gives  up  3  atoms 
of  O  to  3  atoms  of  SO2,  thus 
making  3  atoms  of  SO3,  and 

5 


98  ELEMENTARY  CHEMISTRY. 

becoming  itself  NO2.     Not 
content  with  the  work  now     NO2  +  2  O  -j-  2  SO 
done,  in  its  anxiety  to  sup- 
ply the  wants  of  the  SO2,  the 
NO2  goes  to  the  air  present 
in  the  room,  takes   up   2 
atoms  of  O,  becoming  NO4,    NO,     +        2  S03 
and  flies  back  with  them 

to  the  SO2,  making  2  atoms  more  of  SO3,  then 
turns  to  the  air  again  for  a  fresh  supply.  It  thus 
carries  the  O  back  and  forth  to  such  an  extent 
that  a  small  quantity  of  NO5,  introduced  in  the 
beginning,  will  make  an  almost  unlimited  amount  of 
SO3.  The  steam  hastens  the  chemical  operation 
by  its  warmth  and  moisture.  There  is  a  thin 
layer  of  HO  on  the  floor.  This  absorbs  the  SO3, 
and  is  gradually  drawn  off  and  condensed  by 
evaporation  in  lead  pans,  and  finally,  when  the 
SO3  begins  to  corrode  the  lead,  in  large  platinum 
vessels.  It  is  lastly  put  in  large  bottles  packed  in 
boxes  called  carboys,  when  it  is  ready  for  transpor- 
tation. 

Properties. — It  is  a  dense  oily  liquid,  without  odor, 
and  of  a  brownish  color.  It  freezes  at  30°  and  boils 
at  640°.  It  is  a  hydrate,  containing  one  atom  of 
HO  to  one  of  SO3,  thus  SO3.HO.  Its  affinity  for 
moisture  is  most  remarkable.  If  exposed  in  an  open 
bottle  it  gradually  absorbs  the  water  of  the  air,  and 
increases  in  bulk.  It  will  in  time  double  its  weight 
in  this  way.  It  blackens  wood  and  other  organic 


SULPHUR.  99 

substances,  by  taking  away  their  HO  and  leaving 
the  C.  "When  SO3  is  mixed  with  HO,  it  occupies 
less  space  than  before,  and  liberates  much  heat; 
4  parts  of  acid  to  1  of  HO  will  boil  a  test-tube  of 
HO.  It  commonly  contains  lead,  which  falls  as  a 
milky  precipitate  when  the  acid  is  mixed  with  HO. 
It  is  the  strongest  of  the  acids,  and  will  displace  the 
others  from  their  compounds.  It  stains  cloth  red, 
but  the  color  can  be  restored  with  any  alkali  ; — NaO. 
C02  is  best.  Its  test  is  chloride  of  barium,  which 
forms  a  beautiful  white  cloudy  precipitate.  In  this 
way  a  drop  of  SO3  in  a  quart  of  HO  can  be  distinctly 
detected.  Experiment :  Strong  oil  of  vitriol  poured 
on  a  little  loaf-sugar  moistened  with  hot  water,  will 
cause  an  energetic  boiling  and  a  copious  formation 
of  black  charcoal.  Sugar  consists  of  water  and 
charcoal,  and  gives  up  all  the  former  to  satisfy  the 
appetite  of  the  S03. 

NORDHAUSEN  Aero  is  the  ancient  oil  of  vitriol  made 
in  Germany  from  green  vitriol.  It  is  the  strongest 
sulphuric  acid  known,  and  may  be  separated  from  its 
HO  by  distillation,  when  the  acid  will  appear  as 
white  silky  flakes,  which  may  be  handled  with  im- 
punity, and  will  hiss  when  thrown  into  HO. 

SULPHIDE  OF  HYDROGEN  (HS)  —  Sulphuretted  Hy- 
drogen.— This  gas  is  produced  in  the  decay  of  organic 
matter,  and  is  always  found  near  cesspools,  drains, 
and  sinks,  turning  the  paint  black  and  emitting  a  dis- 
agreeable smell.  It  gives  the  characteristic  odor  to 
the  mineral  waters  of  Avon,  Clifton,  Sharon,  and 


100  ELEMENTARY  CHEMISTRY. 

Saratoga.    It  is  prepared  by  the  action  of  dilute  SCK 
upon  sulphuret  of  iron. 


Making  HS. 

S03 .  HO  I-  FeS 


FeO  .  SO3  +  HS 

It  has  the  disgusting  odor  of  rotten  eggs,  is  very 
poisonous,  and,  therefore,  makes  an  open  sewer  very 
destructive  to  health.  Its  solution  in  HO  is  much 
used  in  the  laboratory  to  precipitate  the  metals  as 
a  black  sulphuret.  Its  test  is  acetate  of  lead  (sugar 
of  lead). 

BISULPHIDE  OF  CARBON  (€82)  is  produced  by  passing 
the  vapor  of  S  over  red-hot  coals.  It  is  a  volatile, 
colorless  liquid,  and  has  never  been  frozen.  It  is 
strange  that  a  yellow  odorless  solid  should  unite 
with  a  black  odorless  solid  to  form  such  a  colorless 
odoriferous  liquid ;  it  thus  illustrates  very  finely  the 


PHOSPHORUS. 


101 


power  of  chemical  affinity.  It  readily  dissolves  sul- 
phur, phosphorus,  and  iodine.  It  is  a  powerful  re- 
fractor of  light,  and  is  used  for  filling  hollow  glass 
prisms — the  most  perfect  known — for  experiments 
with  the  solar  spectrum. 


PHOSPHORUS. 

Symbol,  P--.  Equivalent,  31  ...-Specific  Gravity,  1.83. 

Its  name  signifies  light-bearer,  given  because  of  its 
glowing  in  the  dark.  It  was  called  by  the  old  al- 
chemists, "  the  son  of  Satan." 

Sources. — It  exists  in  small  quantities  in  rocks,  and 
by  their  decay  passes  into 
the  soil,  is  taken  up  by 
plants,  is  then  stored  in  their 
seeds  (wheat,  corn,  oats,  etc.), 
and  finally  passes  into  our 
system.  As  a  phosphate  of 
lime,  it  is  the  principal  con- 
stituent of  our  bones.  As 
pure  P,  it  is  so  necessary  to  Manufacture  of  p. 

the  operation  of  the  brain  that  the  alchemists  had  a 
saying,  "  No  phosphorus,  no  brains." 

Preparation. — It  is  prepared  in  immense  quantities 
from  bones.  These  are  first  calcined  to  whiteness 
to  burn  out  the  animal  matter,  then  treated  with  SO3 
to  remove  the  lime,  and  lastly  heated  to  a  high  tem- 
perature with  C  to  deoxydize  them,  when  the  P 
distils  as  a  vapor,  which  is  condensed  under  HO. 


102  ELEMENTARY  CHEMISTRY. 

Properties. — It  is  a  waxy,  transparent  solid,  at  all 
temperatures  above  32°  emits  a  feeble  light,  and  at 
60°  bursts  into  a  flame.  It  is  therefore  so  combus- 
tible that  it  should  be  handled  with  the  utmost  care, 
always"  kept  and  cut  under  HO,  and  never  used  ex- 
cept in  very  small  quantities.  Its  burns  are  deep 
and  dangerous.  It  is  very  poisonous,  and  is  the  basis 
of  all  rat-exterminators.  Its  vapor  produces  hor- 
rible ulcerations  of  the  jaw-bone  in  workmen  who 
use  it.  In  burning,  it  unites  with  five  atoms  of  O, 
forming  phosphoric  acid  (PO5).  Its  compounds  are 
called  phosphates. 

Amorphous  Form. — Heated  for  48  hours,  at  a  tem- 
perature of  480°,  in  a  close  vessel,  P  is  changed  into 
a  brick-red  powder,  which  seems  to  have  lost  all  the 
properties  of  P.  It  can  be  handled  with  impunity, 
and  carried  in  the  pocket  like  so  much  snuff.  By 
heating  it  again  to  a  higher  point,  it  goes  back  to  its 
old  form. 

Uses. — MATCHES. — The  principal  use  of  P  is  in  the 
making  of  matches.  The  match  is  first  dipped  in 
melted  sulphur  and  dried,  then  in  a  paste  of  P,  nitre 
and  glue,  which  completes  the  process.  The  object  of 
the  nitre  is  to  furnish  O  to  quicken  the  combustion. 
Instead  of  this,  chlorate  of  potash  is  sometimes  used, 
and  can  be  recognized  by  the  crackling  sound  and 
jets  of  flame  when  ignited.  The  tips  are  colored 
by  red-lead,  or  Prussian  blue,  mixed  in  the  paste. 
When  a  match  is  burned,  the  reaction  is  as  follows: 
first,,  the.  fiction  ignites,  the  P,  which  bumsy  farming 


PHOSPHORUS.  103 

PO5;  this  produces  heat  enough  to  inflame  the  S, 
which  makes  SO2;  lastly,  the  wood  takes  fire,  and 
forms  CO2  and  HO.  Thus  there  are  four  compounds 
produced  in  the  ignition  of  a  single  match.  During 
the  burning  of  the  S,  the  value  of  the  match  is  en- 
tirely prospective,  as  the  SO2  is  not  a  supporter  of 
combustion. 

PHOSPHORESCENCE. — The  luminous  appearance  of 
putrefying  fish  and  decayed  wood  are  well  known. 
The  latter  is  sometimes  called  "fox-fire."  The 
"  glow-worm's  fitful  light"  is  associated  with  our  mem- 
ory of  beautiful  summer  evenings.  In  the  West  In- 
dies, fire-flies  are  found  that  emit  a  green  light  when 
resting,  and  a  red  one  when  flying.  These  are  so  bril- 
liant that  one  will  furnish  light  enough  for  reading. 
The  natives  wear  them  for  ornaments  on  their  bon- 
nets, and  illuminate  their  houses  by  suspending  them 
as  lamps. — The  ocean,  at  times,  takes  on  strange 
colors,  and  the  sailor  finds  his  vessel  plowing  at  one 
time  apparently  a  furrow  of  fire,  and  at  another  one 
of  liquid  gold.  The  water  is  all  aglow,  and  the  flames 
seem  to  leap  and  dance  with  the  waves  or  the  motion 
of  the  ship.  These  phenomena  are  produced  by 
multitudes  of  animalculse  which  frequent  certain 
seas.  Phosphorescence  is  generally  attributed  to 
the  gradual  oxydation  of  the  phosphorus  secreted 
by  the  animal  or  plant. 

PHOSPHURETTED  HYDROGEN  (PH3)  is  formed  in  the 
decomposition  of  bones  and  organic  substances.  With 
HS  it  gives  rise  to  the  odor  of  slaughter-houses.  It 


104  ELEMENTAKY  CHEMISTKY. 

is  a  poisonous  gas,  remarkable  only  for  its  disgust- 
ing odor  and  the  singular  beauty  of  the  rings  formed 
by  its  smoke  ascending  through  the  air.  It  is  pre- 
pared by  dropping  bits  of  phosphuret  of  calcium  into 
HO.  It  has  been  thought  by  some  that  the  Will-o'- 
wisp,  Jack-o'-the-lantern,  etc.,  as  seen  near  grave- 
yards and  in  swampy  places,  is  produced  by  this  gas 
coming  off  from  decaying  substances,  and  igniting  as 
it  reaches  the  air. 


THE  METALS. 
THE  METALS  OF  THE  ALKALIES. 

These  are  potassium,  sodium,  lithium,  and  ammo- 
nium. The  last  two  are  of  no  general  interest. 

POTASSIUM. 

Symbol,  K  ••••  Equivalent,  39  ••••  Specific  Gravity,  0.85. 

Source. — This  metal  was  discovered  by  Sir  Humph- 
rey Davy,  in  1807>  by  the  decomposing  action  of  a 
powerful  galvanic  battery.  By  passing  the  current 
through  potassa  (KO),  the  K  went  to  the  negative 
pole,  and  the  O  to  the  positive.  In  the  same  manner 
he  separated  the  metals  sodium,  barium,  strontium, 
and  calcium.  This  discovery  constituted  a  most  im- 
portant epoch  in  chemistry.  K  is  found  abundantly 
in  nature  in  the  various  rocks  which,  by  their  decom- 


POTASSIUM.  105 

position,  furnish  it  to  the  plants,  from  whence  we 
obtain  our  entire  supply. 

Properties. — It  is  a  silvery-white  metal,  soft  like 
wax,  and  light  enough  to  float  like  cork.  Its  affinity 
for  O  is  so  great,  that  it  is  always  kept  under  the 
surface  of  naphtha,  which  contains  no  O.  K,  when 
thrown  on  HO,  decomposes  it,  unites  with  its  O, 
forming  KG,  and  sets  free  the  H. 
The  heat  developed  is  so  great, 
that  the  H  catches  fire  and  burns 

With     SOme    Volatilized    K,     which         Potassium  on  water. 

tinges  the  flame  with  a  beautiful  purple  tint.  If  the 
HO  be  first  colored  with  red  litmus,  it  will  become 
blue  by  the  alkali  (KO)  formed. 

POTASSA  (KO) — Potash. — This  is  a  grayish-white 
solid,  made  from  KO.CO2  by  the  action  of  lime.  It 
is  the  most  powerful  alkali.  It  neutralizes  the  acids, 
and  turns  red  litmus  to  blue.  It  is  used  to  cauterize 
the  flesh,  and  is  hence  commonly  called  "  caustic 
potash."  It  dissolves  the  cuticle  of  the  finger  which 
touches  it,  and  so  has  an  unctuous  feel,  as  we  see  in 
strong  soap.  It  unites  with  grease,  forming  soap, 
and  is  extensively  used  for  that  purpose.  Its  affinity 
for  HO  is  so  great,  that  it  is  never  known  except  as 
a  hydrate  (KO .  HO).  It  also  absorbs  CO2  from  the 
air,  and  must  be  kept  in  close-stoppered  bottles.  It 
is  a  corrosive,  deadly  poison.  Its  test  is  bichloride 
of  platinum,  forming  a  yellow  precipitate  from  a  so- 
lution. 

CARBONATE  OF  POTASH  (KO.C02) — Pearlash. — Pot- 

5* 


106  ELEMENTARY   CHEMISTRY. 

ash  is  contained  in  plants,  combined  with  various 
acids,  such  as  tartaric,  malic,  oxalic,  etc.  When  the 
wood  is  burned,  the  CO2  of  the  fire  drives  off  these 
acids,  and  combines  with  the  KO,  forming  KO.CO2. 
The  ashes  are  then  leached,  and  the  lye  which  is 
formed  is  evaporated  until  the  KO.CO2  crystallizes. 
Birch  gives  the  purest  potash,  while  the  leaves  fur- 
nish 25  times  as  much  as  the  heart  of  a  tree.  Where 
wood  is  abundant,  immense  quantities  are  burned 
solely  for  the  ashes.  Saleratus  is  a  bicarbonate  of 
potash  (KO.2CO2),  and  is  formed  by  passing  a  current 
of  C02  through  the  carbonate. 

NITRATE  or  POTASH  (KO.NO5) — Saltpetre :  Nitre. — 
This  salt  is  found  abundantly  in  Egypt  and  the  East 
Indies,  mixed  with  the  soil.  It  is  obtained  thence  by 
leaching.  It  is  formed  artificially  by  piling  up  great 
heaps  of  mortar,  refuse  of  sinks,  stables,  etc.  In 
about  three  years  these  are  washed,  and  each  cubic 
foot  of  the  mixture  will  furnish  four  or  five  ounces 
of  saltpetre.  It  was  manufactured  in  the  Mammoth 
Cave,  Kentucky,  during  the  war  of  1812.  It  dissolves 
in  one-third  of  its  weight  of  hot  water. 

Properties  and  Uses. — It  is  cooling  and  an  antisep- 
tic :  hence  it  is  used  for  salting  meat,  to  which  it 
gives  a  reddish  tint.  It  parts  with  its  O  readily  and 
burns  brilliantly.  Every  government  keeps  a  large 
supply  on  hand  for  making  gunpowder,  in  the  event 
of  war.  Gunpowder  is  composed  of  three  parts  char- 
coal, and  one  each  of  saltpetre  and  sulphur.  Its 
explosive  force  is  due  to  the  expansive  power  of  the 


SODIUM.  107 

gases  formed.  The  combustion  is  started  by  the 
saltpetre  giving  up  all  its  O  to  burn  the  S  and  C. 
The  reaction  that  ensues  may  be  very  simply  stated 
as  follows : 

KO.NOS  +  S  4-  30 


KB  +  N  +       3CO2 

N  and  CO2  are  gases,  and  in  that  great  heat  of 
nearly  2,000°,  high  enough  to  melt  gold  or  copper, 
the  KS  becomes  a  vapor.  With  the  sudden  increase 
of  temperature,  they  expand  till  they  occupy  2,000 
times  the  space  of  the  powder.  The  bad  odor  of 
burnt  pojvder  is  due  to  the  slow  formation  of  HS 
in  the  residuum.  Fireworks  are  composed  of  gun- 
powder ground  with  additional  C  and  S,  and  some 
coloring  matter.  Zinc  filings  produce  green  stars, 
steel  filings  variegated  ones,  A  little  chlorate  of 
potassa  tinges  the  flame  with  crimson.  Salts  of 
copper  give  a  blue  or  a  green  light,  and  camphor  a 
pure  white  one. 

SODIUM. 
Symbol,  Ma----  Equivalent,  23  ....  Specific  Gravity,  0.972. 

This  metal  is  found  principally  in  common  salt. 
It  is  very  like  K  in  its  appearance,  properties,  and 
reaction.  When  thrown  on  HO  it  rolls  over  its  sur- 
face like  a  beautiful  little  silver  ball :  if 'the  HO  be 
heated,  it  bursts  into  a  yellowish  blaze.  The  test  of 


108  ELEMENTARY  CHEMISTRY. 

all  the  soda  salts  is  the  yellow  tint  which  their  solu- 
tion in  alcohol  gives  to  the  flame. 

CHLORIDE  OF  SODIUM  (NaCl),  common  salt,  is  the 
only  mineral  substance  which  is  absolutely  necessary 
to  the  life  alike  of  all  human  beings  and  the  higher 
order  of  animals.  Among  the  many  cruel  punish- 
ments inflicted  in  China,  deprivation  of  salt  is  said 
to  be  one,  causing  at  first  a  most  indescribable  long- 
ing and  anxiety,  and  finally  a  painful  death.  Dr. 
Draper  tells  us  that  the  salt  and  the  HO  in  the 
stomach  undergo  the  following  reaction  : 

NaCl  +  HO 


IXF 

NaO+HCl 


Both  these  are  essential  in  forming  gastric  juice 
and  bile,  and  to  make  enough  of  them  to  keep  up 
the  proper  digestion  of  our  food,  requires  about  one- 
third  of  an  ounce  of  NaCl.  As  salt  is  so  universally 
necessary,  it  is  found  everywhere.  Our  Father,  in 
fitting  up  a  home  for  us,  did  not  forget  to  provide 
for  all  our  wants.  The  quantity  of  salt  in  the  ocean 
is  said  to  be  equal  to  five  times  the  mass  of  the  Alps. 
Salt  lakes  are  scattered  here  and  there ;  saline  springs 
abound ;  and  besides  these,  in  the  earth  are  stored 
great  mines,  probably  produced  by  the  evaporation 
of  salt  lakes  in  some  ancient  period  of  the  earth's 
history.  At  Cracow,  Poland,  is  a  bed  twelve  hun- 
dred miles  long,  twenty  miles  wide,  and  a  quarter 


SODIUM. 


109 


of  a  mile  thick.  In  Spain,  and  lately  in  Idaho,  it 
has  been  quarried  out  in  perfect  cubes,  transparent 
as  glass,  so  that  a  person  can  read  through  a  large 
mass.  On  the  sea-shore  it  is  manufactured  by  the 
evaporation  of  sea-water,  each  gallon  containing 
about  four  ounces.  At  Syracuse,  New  York,  near 
by  and  underneath  the  Onondaga  Lake,  is  appa- 
rently a  great  basin  of  salt-water,  separated  from 
the  fresh-water  above  by  an  impervious  bed  of  clay. 
Penetrating  this  to  a  depth  of  about  seven  hundred 
feet,  the  saline  water  is  pumped  up  in  immense 
quantities.  The  State  sells  this  to  salt  manufactur- 
ers, on  the  payment  of  a  cent  per  bushel  on  the  salt 
made.  The  HO  is  evaporated  by  heating  in  large 
iron  kettles  or  vats,  or  in  the  sun,  whence  the  name 
"solar  salt."  If  boiled  down  rapidly,  fine  table- 
salt  is  made ;  if  more  slowly,  coarse  salt,  as  large 
crystals  have  time  to  form.  Frequently  they  assume 
a  "hopper  shape" — one  cube  appears,  then  others 


Hopper  Form. 


110  ELEMENTAEY   CHEMISTEY. 

collect  at  its  edges,  and  gradually  settle,  until  a  hol- 
low pyramid  of  salt-cubes,  with  its  apex  downward, 
is  formed.  About  seven  million  barrels  are  made 
annually  at  this  city.  Salt  dissolves  equally  well  in 
hot  or  in  cold  water,  and  a  saturated  solution  (one 
containing  all  it  will  dissolve)  has  37  per  cent, 
of  salt. 

SULPHATE  OF  SODA  (NaO.SO3),  Glauber's  salts, 
named  from  the  discoverer,  is  made  from  common 
gait. 

NaCl  +    HO.SOs 


NaO.SO3  +  HC1 

Experiment :  Make  a  saturated  solution  of  sulphate 
of  soda,  and  with  it  fill  a  bottle.  Either  put  in  the 
glass  stopple  or  cover  the  top  with  a  thin  layer  ot 
oil,  and  let  the  bottle  stand.  The  salts  will  remain 
for  weeks  or  even  months  without  crystallizing  ;  but 
if  they  be  taken  up,  and  shaken  ever  so  little,  the 
whole  mass  will  instantly  form  into  crystals,  so  fill- 
ing the  bottle  that  not  a  drop  of  water  will  escape, 
even  if  it  be  inverted.  Should  there  be  any  hesita- 
tion in  crystallizing  at  the  moment,  drop  into  the 
bottle  a  minute  crystal  of  Glauber's  Salts,  and  the 
effect  will  instantly  be  seen  in  the  darting  of  new 
crystals  in  every  direction. 

CABBONATE  OF  SODA  (NaO.CO2),  sal-soda,  is  used 
in  immense  quantities  in  the  manufacture  of  glass, 


SODIUM.  Ill 

soap,  etc.  (See  Appendix,  Problem  40.)  It  is  em- 
ployed, like  borax,  to  soften  hard  water,  by  com- 
bining with  the  lime  and  magnesia,  and  making 
insoluble  carbonates,  which  settle  to  the  bottom. 
In  washing,  it  unites  with  the  grease  in  the  clothes, 
and  forms  soap. 

BICARBONATE  OF  SODA  (NaO .  2  CO2)  is  the  "  soda'1 
of  the  cook-room,  and  is  formed,  like  saleratus,  from 
its  carbonate. 

SILICATE  OF  SODA  AND  LIME  (NaO.SiO2  4-  CaO. 
SiO2) — French  plate  and  window  glass.  Glass  was 
known  to  the  ancients.  Hieroglyphics,  that  are  as 
old  as  the  sojourn  of  the  Israelites  in  Egypt,  repre- 
sent glass-blowers  at  work,  much  after  the  fashion 
of  the  present.  In  the  ruins  of  Nineveh,  articles 
of  glass,  such  as  vases,  lenses,  etc.,  have  been 
discovered.  Mummies,  three  thousand  years  old, 
are  adorned  with  glass  beads.  The  inventor  is 
not  known.  Pliny  tells  us  that  some  merchants, 
once  encamping  on  the  sea-shore,  found  in  the 
remains  of  their  fire  bits  of  glass,  formed  from 
the  sand  and  ashes  of  the  sea-weed  by  the  heat ; 
but  this  is  impossible,  as  an  open  fire  could  not  be 
sufficient  to  melt  these  materials.  In  the  fourth 
century,  the  glass-works  at  Alexandria  produced 
most  exquisite  ornaments,  with  raised  figures  beau- 
tifully cut  and  gilded.  As  late,  however,  as  the 
twelfth  century,  a  house  with  glass  windows  was 
esteemed  something  magnificent ;  and  we  read  that 
in  1577,  during  Queen  Elizabeth's  reign,  when  the 


112  ELEMENTARY  CHEMISTRY. 

Duke  of  Northumberland  came  to  town  to  pass  the 
winter,  the  windows  of  his  castle  were  taken  out  and 
packed  away  for  safe-keeping  until  spring. 

Preparation. — Glass  is  a  double  silicate,  being 
composed  of  silica  and  any  two  of  the  alkaline  bases, 
lime,  soda,  potash,  or  magnesia.  Example  :  Fine 
white  sand  is  mixed  with  sal-soda  and  lime,  and 
then  heated  in  earthen  pots  to  the  most  intense 
degree  for  forty-eight  hours.  The  materials  fuse 
and  form  a  double  silicate  of  soda  and  lime.  This 
is  common  window-glass.  A  variation  in  the  ma- 
terials used  produces  different  kinds  of  glass.  The 
only  essential  ingredients  are  sand  and  soda  or  sand 
and  potassa.  Lime  hardens  and  gives  lustre,  while 
soda  imparts  a  green  tint.  Arsenic  whitens  it. 
Oxyd  of  lead  is  used  in  large  quantities,  as  high  as 
one-half  the  weight,  to  form  a  soft  glass,  which  can 
be  ground  into  imitation  gems,  table-ware,  chande- 
lier pendants,  prisms,  etc.  Oxyd  of  iron  gives  an 
opaque  green,  as  in  common  junk  or  green  glass 
bottles.  Boracic  acid  increases  the  refractive  power 
for  lenses  in  microscopes  and  telescopes. 

Bohemian  glass  is  a  silicate  of  potash  and  lime, 
and  thus  does  not  show  the  green  tint  of  soda.  Pul- 
verized flint  was  formerly  used  for  sand,  and  hence 
the  term  flint-glass. 

COLORED  GLASS. — A  small  quantity  of  some  metallic 
Oxyd,  melted  with  the  glass,  gives  any  tint  desired : 
AuO  gives  a  ruby  red ;  MnO,  an  amethyst ;  CuO,  an 
azure  blue;  As  and  Sb  a  soft  white  enamel,  as  in 


SODIUM.  113 

lamp-shades;  SnO2,  a  hard  enamel,  as  in  watch- 
faces. 

ANNEALING  GLASS. — If  the  glass  utensils  were  im- 
mediately used,  they  would  be  found  extremely  brit- 
tle, and  would  drop  in  pieces  in  the  most  unaccount- 
able way.  The  heat  of  the  hand  or  a  draft  of  cool 
air  would  sometimes  crack  off  the  thick  bottom  of  a 
tumbler.  They  are  therefore  cooled  very  gradually 
for  days,  which  allows  the  particles  to  assume  their 
natural  place,  and  the  chemical  attractions  to  become 
equalized.  This  principle  is  beautifully  illustrated 
by  the  chemical  toy  known  as  the  "  Prince  Kupert 
Drop." 

ORNAMENTAL  WABE. —  Venetian  balls  or  paper 
weights  are  made  by  arranging  bits  of  colored  glass 
in  the  form  of  fruits,  flowers,  etc.,  and  then,  inserting 
this  ball  into  a  hollow  globe  of  transparent  glass,  still 
hot,  the  workman  draws  in  his  breath,  and  the 
pressure  of  the  air  above  collapses  the  globe  upon 
the  colored  glass,  and  leaves  a  concave  surface  in 
the  top  of  the  weight.  The  lens  form  always  magni- 
fies the  size  of  the  figures  within. 

TUBES  AND  BEADS. — In  making  glass  tubing,  the 
workman  inserts  his  iron  blowing-tul^e  into  a  pot  of 
melted  glass,  and  gathers  upon  the  end  a  suitable 
amount :  drawing  this  out,  he  blows  into  the  tube, 
swelling  the  glass  into  a  globular  form.  Another 
dip  into  the  pot  and  another  blow  increase  its  size, 
until  at  last  a  second  workman  attaches  an  iron  rod 
to  the  other  end.  The  two  men  then  separate  on  a 


114  ELEMENTARY  CHEMISTRY. 

rapid  trot.  The  soft  glass  globe  diminishes  in  size 
as  it  lengthens,  until  at  last  it  hangs  between  them 
a  glass  tube  of  one  hundred  feet  in  length,  and  per- 
haps only  a  quarter  of  an  inch  in  diameter.  In 
making  beads,  these  glass  tubes  are  cut  in  small  bits, 
and  then  worked  about  in  a  mixture  of  wet  ashes 
and  sand,  until  they  are  filled.  Next  they  are  put 
with  loose  sand  into  a  rapidly-revolving  cylinder 
over  a  hot  furnace.  The  heat  softens  the  glass,  but 
the  mixture  within  presses  out  the  sides,  and  the 
sand  grinds  the  edges,  until  at  last  the  beads  be- 
come round  and  perfect,  and  are  taken  out  ready  for 
market. 

AMMONIUM. 

AMMONIUM  (NH4)  has  never  been  separated,  but  is 
thought  to  be  the  base  of  ammonia  (NH3).  In  com- 
bination NH3  combines  with  an  atom  of  HO,  becom- 
ing NH3 .  HO  =  NH4 . 0.  This  is  considered  as  the 
oxyd  of  the  compound  radical  ammonium.  Ex- 
ample :  NO5  +  HO  +  NH3  uniting,  form  NH3.HO. 


CALCIUM.  115 


METALS  OF  THE  ALKALINE  EARTHS. 

These  are  Ba,  Ca,  and  Mg,  but  the  last  two  only 
are  of  general  interest. 

CALCIUM. 

Symbol,  Ca  -  -Equivalent,  20- ••  -Specific  Gravity,  1.57. 

This  metal  exists  abundantly  in  limestone,  gyp- 
sum, and,  combined  with  phosphoric  acid,  in  the 
bones  of  the  body.  It  is  commonly  known  only  as 
an  oxyd-lime. 

CaO  (CAUSTIC  or  QUICKLIME)  is  obtained  by  heating 
limestone  (CaO.CO2)  in  large  kilns.  The  CO2  is 
driven  off  by  the  heat,  and  leaves  the  lime  as  a 
white  solid. 

Properties. — It  is  a  strong  alkali,  and  corrodes  the 
flesh.  Its  test  is  CO2,  producing  a  milky  precipitate 
of  CaO.CO2.  It  has  such  a  strong  affinity  for  HO, 
that  28  Ibs.  of  lime  will  absorb  9  Ibs.  of  HO,  forming 
CaO.HO,  or  "  slacked  lime,"  and  swelling  up  to  three 
times  its  original  size,  with  the  evolution  of  much 
heat.  It  absorbs  HO  from  the  air,  and  then  CO2, 
thus  gradually  becoming  a  carbonate  of  lime — "  air- 
slacked  lime."  It  is  more  soluble  in  cold  than  hot 
water.  A  thin  film  of  carbonate  of  lime  will  soon 
gather  over  a  solution  of  lime  exposed  to  the  air. 

Uses. — It  is  used  in  tanning  leather  to  remove  the 
hair.  Whitewash  is  a  "  milk  of  lime" — if  e.,  a  mixture 
of  CaO  and  HO.  In  mortar,  lime  hardens  rapidly, 


116  ELEMENTARY  CHEMISTRY. 

in  part  by  uniting  with  the  silica  of  the  sand  to  form 
a  silicate,  and  also  by  absorbing  CO2  from  the  air  to 
form  carbonate  of  lime.  In  this  process,  the  HO 
which  the  lime  absorbed  in  slacking  is  given  off ;  this 
causes  the  dampness  always  seen  on  newly-plastered 
walls  when  the  room  is  first  warmed.  For  drying 
plastering  it  would  be  much  better  if  the  CO2  of  the 
fire  could  be  sent  directly  into  the  room,  as  it  would 
hasten  the  chemical  change.  "  If  common  mortar  be 
protected  from  the  air  it  will  remain  without  harden- 
ing for  many  years.  It  is  stated  that  lime  still  in  the 
condition  of  a  hydrate  has  been  found  in  the  pyra- 
mids of  Egypt.  When  the  ruins  of  the  old  castle 
of  Landsberg  were  removed,  a  lime-pit,  that  must 
have  been  in  existence  300  years,  was  found  in  one 
of  the  vaults.  The  surface  was  carbonated  to  the 
depth  of  a  few  inches,  but  the  lime  below  this  was 
fresh  as  if  just  slacked,  and  was  used  in  laying  the 
foundations  of  the  new  building."  (Am.  Cyc.) 

If  the  lime  contains  a  little  clay,  it  is  called  water- 
lime,  and  will  harden  under  water.  Lime  is  valuable 
as  a  fertilizer.  It  acts  by  rapidly  decomposing  all 
vegetable  matter,  and  thus  forming  ammonia  for  the 
use  of  plants.  It  also  sets  free  the  alkalies  that  are 
combined  with  silica  in  the  soil,  and  furnishes  them 
to  the  plants.  It  does  not  itself  feed  the  plants,  as 
almost  any  soil  contains  enough  lime  for  that  purpose. 
If  applied  to  a  compost  heap,  it  will  set  free  am- 
monia, which  can  be  recognized  by  the  odor:  this 
is  its  most  valuable  constituent.  The  NH3  can  be 


CALCIUM.  117 

saved  by  sprinkling  the  heap  with  very  dilute  SO3, 
or  plaster,  or  by  mixing  it  with  dry  muck,  which  will 
absorb  the  gas.  If  there  is  any  copperas  (produced 
by  the  oxydation  of  iron  pyrites)  in  the  soil,  the  lime 
will  decompose  it,  forming  gypsum  and  iron-rust 
(CaO.SO3  +  Fe2O3),  thus  changing  a  noxious  ingre- 
dient into  an  element  of  fertility. 

CABBONATE  OF  LIME. — This  includes  all  varieties 
of  common  limestone,  chalk,  marble,  marl,  and  forms 
the  principal  part  of  corals,  shells,  and  bones.  Water 
charged  with  CO2  absorbs  carbonate  of  lime  freely, 
which,  when  the  gas  escapes  on  exposure  to  the 
air,  is  deposited.  In  this  manner,  in  limestone 
regions,  the  water  trickling  down  into  caverns  has 


A  Cave. 

formed  "  stalactites,"  which  depend  from  the  ceiling, 
and  "  stalagmites,"  that  rise  from  the  floor.  These 
frequently  assume  most  curious  and  grotesque  forms, 
as  in  the  Mammoth  Cave.  Around  many  springs, 
the  water,  charged  with  lime  in  solution,  flows  over 
moss  or  some  vegetable  substance,  upon  which  the 


118  ELEMENTARY  CHEMISTRY. 

lime  is  deposited.  The  spongy  stone  thus  formed 
is  calcareous  tufa,  or  "petrified  moss."  Whiting  is  a 
carbonate  of  lime,  made  by  grinding  chalk.  MairUe 
is  crystallized  limestone.  C/ialk  or  marl  is  a  porous 
kind  of  limestone,  formed  from  beds  of  shells,  but  not 
compressed  as  in  common  limestone.  These  minute 
shells  may  be  detected  by  a  powerful  microscope,  even 
in  glazing  scraped  from  a  common  visiting  card. 

SULPHATE  OF  LIME  (CaO.SO3) — Gypsum,  Plaster, 
etc. — This  occurs  as  beautiful  fibrous  crystals  in  satin 
spar,  as  transparent  plates  in  selenite,  and  as  a 
snowy-white  solid  in  alabaster.  It  is  soft,  and  can 
be  cut  into  rings,  vases,  etc.  When  heated  it  loses 
its  water  of  crystallization,  and  falls  into  powder, 
called  "  Plaster  of  Paris,"  from  its  abundance  near 
that  city.  Made  into  a  paste  with  HO,  it  first  swells 
up,  and  then  immediately  hardens  into  a  solid  mass. 
This  property  fits  it  for  use  in  copying  medals  and 
statues,  forming  moulds,  fastening  metal  tops  on 
glass  lamps,  etc.  Plaster  is  also  used  as  a  fertilizer. 
Its  action  is  probably  somewhat  like  that  of  lime, 
and  in  addition  it  gathers  up  ammonia  and  holds  it 
for  the  plant.  It  is  said  that  Franklin  brought  it 
into  use  by  sowing  it  over  a  field  of  grain  on  the  hill- 
side, so  as  to  form,  in  gigantic  letters,  the  sentence, 
"  Effects  of  gypsum."  The  rapid  growth  produced 
soon  brought  out  the  words  in  bold  relief,  and  decided 
the  destiny  of  gypsum  among  farmers.  Sulphite  of 
lime  (CaO.SO2)  should  be  distinguished  from  the  sul- 
phate (CaO.SO3).  This  is  used  for  preserving  cider. 


MAGNESIUM.  119 

PHOSPHATE  OF  LIME  is  contained,  as  Ave  have  al- 
ready seen,  in  bones.  If  now  we  add  to  them  SO3, 
it  will  take  up  a  part  of  the  lime,  making  sulphate 
of  lime  (plaster),  and  the  phosphoric  acid  thus  driven 
off  will  take  refuge  with  the  rest  of  the  acid  and 
share  its  lime,  forming  a  s?^er-phosphate  of  lime. 
This  is  used  very  extensively  as  a  fertilizer,  and  is, 
as  we  have  described,  a  mixture  of  gypsum  or  plas- 
ter, lime,  and  phosphoric  acid.  The  last  furnishes 
phosphorus  to  the  growing  plant  to  store  in  its  seeds. 
Example :  Corn,  wheat.  Phosphate  of  lime  and 
ammonia  are  the  valuable  constituents  of  "  guano." 


MAGNESIUM. 

Symbol,  Mg  •••.  Equivalent,  12  ••••  Specific  Gravity,  1.7. 

Source. — Mg  is '  found  in  many  rocks  as  meer- 
schaum, soapstone,  and  magnesian  limestone,  and  is 
abundant  also  in  sea-water.  It  gives  to  a  stone  a 
soapy  feel.  When  pure,  it  has  a  silvery  appearance 
and  lustre.  It  is  very  light  and  tenacious  as  steel, 
while  it  is  flexible  as  twine.  It  burns  in  the  open 
air  with  a  brilliant  white  light,  casting  dense  shadows 
through  an  ordinary  flame.  This  light  possesses  the 
actinic  or  chemical  principle  so  perfectly,  that  it  is 
used  for  taking  photographs  at  night,  views  of  coal- 
mines, interiors  of  dark  churches,  etc.  It  has  every 
ray  of  the  spectrum,  and  so  does  not,  as  does  gas- 
light, change  some  of  the  colors  of  an  object  upon 


120  ELEMENTARY   CHEMISTRY. 

which  it  falls.  Lamps  for  burning  it  are  veiy  exten- 
sively made  in  Boston.  By  means  of  clockwork,  the 
metal,  in  the  form  of  a  narrow  ribbon,  is  fed  in  front 


Magnesium  Lamp. 


of  a  concave  mirror,  at  the  focus  of  which  it  burns. 
The  product  of  the  combustion  of  Mg  is  MgO,  the 
very  substance  from  which  the  metal  was  obtained. 


ALUMINUM.  121 

It  is  probable  that  the  process  of  preparation  will 
be  cheapened,  so  that  magnesium  may  be  furnished 
at  a  rate  which  will  bring  it  within  the  scope  of  the 
arts.  It  would  be  invaluable  for  lighting  stores  in 
which  fancy  goods  are  sold,  or  for  illuminating  large 
halls  by  means  of  a  single  lamp  suspended  in  the 
dome. 

CARBONATE  OF  MAGNESIA  (MgO.CO2). — This  is  the 
"  magnesia  alba,"  or  simple  magnesia  of  the  druggists. 
By  driving  off  the  CO2,  calcined  Mg  is  formed.  Sul- 
phate of  Mg  (Mg.SO3)  is  known  as  Epsom  salts,  from 
a  celebrated  spring  in  England  in  which  it  abounds. 


METALS  OF  THE  EARTHS. 

These  are  Al,  Gl,  Zr,  Y,  Th,  Er,  Tb,  Ce,  Ln,  D,  In, 
Tl,  Kb,  Cs.  All  are  extremely  rare  except  the  first. 

ALUMINUM. 

Sym.,  AI ....  Equiv.,  13-7  ....Spec.  Grav.,  2.5  ....  Fusing  Pt,  2283°. 

This  is  commonly  called  the  "clay-metal."  It  is 
named  from  alum,  in  which  it  occurs.  It  is  the 
metallic  base  of  all  clay,  argillaceous,  and  granite 
rocks.  It  is  a  bright  white  metal,  does  not  oxydize 
in  the  air,  nor,  like  silver,  tarnish  by  HS.  It  gives 
a  clear  musical  ring ;  is  lighter  than  glass,  being 
only  two  and  a  half  times  as  heavy  as  HO  ;  is  duc- 
tile, malleable,  and  more  tenacious  than  Fe.  It 

6 


122  ELEMENTARY  CHEMISTRY. 

dissolves  in  HC1  or  in  common  vinegar,  but  is  proof 
against  SO3  or  NO3.  On  account  of  its  abundance 
(every  clay-bank  is  a  mine  of  it)  and  useful  properties, 
it  must  ultimately  come  into  common  use  in  the  arts 
and  domestic  life. 

ALUMINA  (A12O3). — Pure  alumina,  crystallized  in 
nature,  forms  valuable  Oriental  gems.  They  are 
variously  colored  by  the  oxyds ; — blue,  in  the  sap- 
phire ;  green,  in  the  emerald  ;  yellow,  in  the  topaz  ; 
red,  in  the  ruby.  Massive  impure  crystals,  when 
powdered,  are  called  emery,  and  are  used  for  pol- 
ishing. 

SILICATE  OF  ALUMINA  (A12  O3 .  Si02) — common  day. 
— When  the  granite  rocks  decay,  by  the  resistless 
and  constant  action  of  the  air,  rain,  and  frost,  they 
crumble  into  clay.  This  gives  firmness  to  the  soil, 
and  retains  moisture,  but  is  cold  and  tardy  in  pro- 
ducing vegetable  growth.  When  free  from  iron,  it 
is  used  for  making  tobacco-pipes.  When  colored 
by  yellow  or  red  oxyd  of  iron,  it  is  known  as  ochre, 
and  is  employed  in  painting.  Common  stone  and 
red  earthen-ware  are  made  from  impure  varieties  of 
clay;  porcelain  and  china-ware  require  the  finest 
known.  Fire-bricks  and  crucibles  are  made  from  a 
clay  which  contains  much  silica.  Fullers'  earth  is 
a  very  porous  kind,  and  by  capillary  attraction  ab- 
sorbs grease  and  oil  from  cloth. 

Glazing. — When  any  article  of  earthenware  has 
been  moulded  from  clay,  it  is  then  baked.  The 
ware  is  now  porous,  and  would  not  even  hold  HO. 


ALUMINUM. 


123 


A  mixture  of  the  coarse  materials  from  Avhich  glass 
is  made  is  then  spread  over  the  vessel,  and  heatec^ 
till  it  melts  and  forms  a  per- 
fect glazing  upon  the  clay. 
NaCl  and  sand  form  the  glaz- 
ing on  stoneware,  jugs,  etc. 
PbO  makes  a  yellowish  glaze, 
which  is  very  injurious,  as  it 
will  dissolve  even  in  vinegar, 
and  form  sugar  of  lead,  a  dead- 
ly poison.  The  color  of  pottery- 
ware  and  brick  is  due  to  the 
oxyd  of  iron  present  in  the 

-,  c*  .    . .         ,  -         Baking  Porcelain. 

clay.     Some  varieties  have  no 

iron,  and  so  form  white  ware  and  brick. 

SULPHATE  OF  ALUMINA  AND  POTASH  (KO.SO3  -f 
A12O3.3SO3  +  24HO).— Alum  is  formed  by  soaking 
clay  with  SO3,  in  large  casks  for  several  months, 
until  the  sulphate  of  alumina  is  formed,  when  potassa 
is  added,  and  the  whole  mass  becomes  filled  with 
crystals  of  the  new  salt.  Instead  of  KO,  other 
bases  are  sometimes  used,  and  an  iron,  soda,  or 
chrome  alum  is  formed.  When  heated,  alum  loses 
its  water  of  crystallization,  froths  up,  and  becomes 
a  porous  mass,  known  as  "  burnt  alum."  Alum  is 
soluble  in  18  parts  of  cold  water.  It  is  much  used 
in  dyeing.  It  unites  with  the  coloring  matter,  and 
binds  it  to  the  fibres  of  the  cloth.  It  is  therefore 
called  a  mordant  (mordeo,  to  bite). 

ALUM  CRYSTALS. — Beautiful   octohedron    crystals 


124  ELEMENTARY  CHEMISTBY. 

of  alum  are  obtained  by  suspending  threads  in  a 
saturated  solution  of  this  salt.  In  this  manner  alum- 
baskets,  bouquets,  etc.,  are  made  of  any  desired 
color. 

SPECTRUM  ANALYSIS. 

Many  of  the  metals  named  as  rare  have  been  lately 
discovered  by  what  is  termed  Spectrum  Analysis. 
We  have  already  noticed  that  various  metals  impart 
a  peculiar  color  to  flame ;  thus  the  soda  salts  give  a 
yellow  tinge,  copper  a  green,  etc.  If  now  we  look 
at  these  colored  flames  through  a  prism,  we  shall  find 
the  "  spectrum,"  or  bands  of  rainbow-colors  we  are 
familiar  with,  strangely  ornamented  with  bright- 
tinted  lines.  Thus  the  spectrum  of  sodium  has  one 
bright  yellow  line  ;  silver,  two  green  lines  ;  caesium, 
a  beautiful  blue  line.  Each  metal  makes  a  distinc- 
tive spectrum,  even  when  the  flame  is  colored  by 
several  substances  at  once.  This  method  of  analysis 
is  so  delicate  that  Y,TTB^,^FO,FF^  °^  a  gramme  of  so- 
dium, or  the  ^o,o"oV, TOT  °^  a  gramme  of  lithium,  can 
be  detected  in  the  flame  of  an  alcohol  lamp. 

For  the  more  perfect  examination  of  the  spectra,  a 
"  spectroscope"  is  used.  This  consists  of  a  tube 
with  a  narrow  slit  at  one  end,  which  lets  only  a  single 
ray  of  colored  light  fall  upon  the  prism  within,  and 
at  the  other  a  small  telescope,  through  which  one 
can  look  in  upon  the  prism  and  examine  the  spec- 
trum. 


IBON.  125 

THE  HEAVY  METALS. 

IBON. 

Symbol,  Fe  ••  Equivalent,  28- •••Specific  Gravity,  7.8. 

Iron  is  the  symbol  of  civilization.  Its  value  in 
the  arts  can  be  measured  only  by  the  progress  of 
the  present  age.  In  its  adaptations  and  employ- 
ments it  has  kept  pace  with  scientific  discoveries  and 
improvements,  so  that  the  uses  of  iron  may  readily 
indicate  the  advancement  of  a  nation.  It  is  worth 
more  to  the  world  than  all  other  metals  combined. 
We  could  dispense  with  gold  or  silver, — they  largely 
minister  to  luxury  and  refinement,  while  iron  repre- 
sents only  the  honest  industry  of  labor.  Its  use  is 
universal,  and  it  is  fitted  alike  for  massive  iron 
cables,  and  for  screws  so  tiny  that  they  can  be  seen 
only  by  the  microscope,  appearing  to  the  naked  eye 
like  grains  of  black  sand. 

"  Iron  vessels  cross  the  ocean, 
Iron  engines  give  them  motion, 
Iron  needles  northward  veering, 
Iron  tillers  vessels  steering, 
Iron  pipes  our  gas  delivers, 
Iron  bridges  span  our  rivers, 
Iron  pens  are  used  for  writing, 
Iron  ink  our  thoughts  inditing, 
Iron  stoves  for  cooking  victuals, 
Iron  ovens,  pots,  and  kettles, 
Iron  horses  draw  our  loads, 
Iron  rails  compose  our  roads, 
Iron  anchors  hold  hi  sands, 


126  ELEMENTARY   CHEMISTRY. 

Iron  bolts  and  rods  and  bands, 

Iron  houses,  iron  walls, 

Iron  cannon,  iron  balls, 

Iron  axes,  knives,  and  chains, 

Iron  augers,  saws,  and  planes, 

Iron  globules  hi  our  blood,* 

Iron  particles  in  food, 

Iron  lightning-rods  on  spires, 

Iron  telegraphic  wires, 

Iron  hammers,  nails,  and  screws, 

Iron  everything  we  use." 

Its  abundance  everywhere  indicates  how  indis- 
pensable the  Creator  deemed  it  to  the  education  and 
development  of  man.  There  is  no  "  California"  of 
iron.  Each  nation  has  its  own  supply.  No  other 
material  is  so  enhanced  by  labor.  A  bar  of  Fe, 
worth  $5,  becomes  worth,  when  made  into  horse- 
shoes, $10 ;  into  needles,  $55 ;  penknives,  $3,285  ; 
shirt -buttons,  $29,480;  and  in  watch  -  springs, 
$240,000,  or  more  than  its  weight  in  gold. 

OXYDS  OF  IRON. — The  most  usual  are :  (1)  BLACK  or 
MAGNETIC  OXYD  OF  IRON  (Fe3O4),  as  found  in  the 
loadstone,  Swedish  iron  ore,  scales  which  fly  off  in 
forging  iron,  and  in  the  iron  mountains  of  Missouri. 
It  is  also  seen  in  the  thin  pellicles  overstanding  HO, 
producing  a  beautiful  iridescent  appearance,  the  color 
changing  with  the  thickness  of  the  oxyd  :  (2)  The 
RED  OXYD  OF  IRON — sesquioxyd — (Fe2O3),  as  seen  in 

*  There  is  not  probably  enough  iron  in  the  blood  of  a  full- 
grown  person  to  make  a  ten-penny  nail,  yet  it  gives  energy  and 
life  to  the  system.  Iron  is  given  in  the  form  of  a  fine  powder,  or 
a  citrate  of  iron,  as  a  tonic,  and  is  a  powerful  remedy. 


IBON. 


127 


bog-iron  ore,  in  the  beautiful  radiated  and  fibrous 
specimens  of  brown  and  red  hematite,  in  bricks  and 
pottery- ware,  and  in  common  iron-rust.  The  sesqui- 
oxyd,  when  combined  with  HO,  forms  (3)  HYDKATED 
SESQUIOXYD  OF  IBON  (Fe2O3.HO),  and  has  a  yellow 
color,  which  is  changed  to  red  by  heat,  when  the  HO 
is  expelled,  as  in  burning  of  brick,  etc.  These  oxyds 
give  the  yellow  and  black  colors  seen  in  clayey  soils 
and  on  the  surface  of  weather-beaten  stones.  The 
black  gradually  oxydizes  into  the  yellow,  and  so  a 
black  stone  forms  a  yellow  sand  or  soil. 

Smelting  of  Iron  Ores. — Iron  is  not  found  pure, 
but  is  locked  up  with  0  in  an  apparently  useless 
stone.  C  is  the  key  that  is  ready  made  and  left  for 
our  use  by  the  Creator.  It  only  remains  for  us  to 
apply  it  and  turn  the  wards. 
The  process  adopted  at  the 
mines  is  very  simple.  A 
tall  blast-furnace  is  con- 
structed of  stone  and  lined 
with  fire-brick.  At  the  top 
is  the  door  and  at  the  bot- 
tom pipes  for  forcing  in  hot 
air,  sometimes  twelve  thou- 
sand cubic  feet  per  minute, 
by  huge  blowing-cylinders 
driven  by  steam-power.  The 
furnace  is  filled  with  lime, 

_    .  .  A  Blast-Furnace. 

stone,  coal,  and  iron  ore,  in 

alternate  layers,  and  the  fire  ignited.  The  C  unites  with 


128  ELEMENTAEY  CHEMISTBY. 

the  O  of  the  ore,  and  goes  off  as  CO2.  The  limestone 
forms,  with  the  other  impurities,  silica,  etc.,  a  richly- 
colored  glassy  slag,  which  rises  to  the  top.  The  melted 
iron  runs  to  the  bottom,  and  is  drawn  off  into  channels 
cut  in  the  sand  on  the  floor  of  ^ie  furnace.  The 
large  main  one  is  called  the  soiv,  and  the  smaller 
lateral  ones  the  pigs,  and  hence  the  term  pig-iron. 

Pr  ope  i  ties. — Iron  when  pure  is  white.  As  com- 
monly seen  it  has  a  gray  tint,  and  is  susceptible  of 
a  high  polish.  It  is  malleable  and  ductile.  It  has 
been  beaten  into  leaves  so  thin  that  it  has  been 
used  for  writing-paper — six  hundred  leaves  being 
only  half  an  inch  in  thickness — and  has  been  drawn 
into  wire  as  fine  as  a  hair.  By  constant  jarring  it 
loses  its  perfect  crystalline  structure,  becoming  rot- 
ten and  brittle,  so  that  the  axles  of  cars,  cannon, 
etc.,  are  condemned  after  a  certain  time,  although 
no  flaw  may  appear.  It  is  an  exception  to  the  law 
that  "  cold  contracts,"  since  at  the  instant  of  solidi- 
fication it  expands,  so  as  to  copy  exactly  every  line 
of  the  mould  in  which  it  is  cast.  This  fits  it  per- 
fectly for  castings.  Almost  the  entire  value  of  iron 
in  the  arts  depends  upon  this  fact.  Otherwise  we 
could  never  hammer  out  enough  tools  and  machinery 
to  keep  the  world  at  work.  Was  it  chance  or  design 
that  contrived  all  this  nice  planning  so  long  even 
before  man  was  made  ? 

Varieties  of  Fe. — The  usual  forms  of  iron  are  cast, 
wrought,  and  steel.  These  depend  upon  the  quantity 
of  C  they  contain.  A  cwt.  of  cast-iron  has  about 


IRON. 


129 


A  Reverberatory  Furnace. 


6  Ibs.  of   C,  a   cwt.  of  wrought  about  J   lb.,  and 
steel  is  between  them  in  varying  quantities. 

CAST  FE  is  the  form  in  which  it  comes  from  the  fur- 
nace. It  is  brittle,  cannot  be  welded,  and  is  neither 
malleable  nor  ductile,  but  is  adapted  for  castings. 

WROUGHT  or  MALLEABLE  FE  is  made  by  burning  out 
the  C  from  cast-iron,  in  a  current  of  highly-heated 
air,  in  what  is  called  a  re- 
verberatory  furnace.  The 
Fe  is  stirred  up  constantly, 
and  exposed  to  the  hot 
air  by  means  of  "  long  pud- 
dling-sticks,"  as  they  are 
termed,  and  then  taken  out 
.and  beaten  under  a  trip- 
hammer to  force  out  all  the  slag,  and  bring  the  par- 
ticles of  Fe  nearer  each  other.  It  now  takes  on  a 
fibrous  structure,  and  can  be  welded,  is  malleable 
and  ductile.  It  is  hardened  by  being  cooled  rapidly, 
and  softened  by  cooling  slowly.  The  blacksmith 
tempers  his  work  by  plunging  the  article  in  cold  HO. 

STEEL  contains  less  C  than  cast  and  more  than 
wrought  iron.  It  is  therefore  made  from  the  formei 
by  taking  out  a  part  of  the  C,  or  from  the  latter  by 
heating  it  in  boxes  of  charcoal,  and  so  adding  C.* 
The  value  of  steel  depends  largely  upon  the  temper- 

*  By  what  is  now  known  extensively  as  "  Bessemer's  process 
of  making  steel,"  it  is  formed  from  pig-iron  without  the  use  of 
fuel.  A  current  of  hot  air  is  carried  up  through  the  liquid  iron, 
which  burns  out  the  carbon,  and  in  its  combustion*  produces  heat 


130  ELEMENTARY   CHEMISTRY. 

ing  quality  it  possesses.  As  the  metal  cools,  the 
film  of  oxyd  on  the  surface  gradually  thickens,  and 
so  deepens  in  color.  By  watching  this  the  workmen 
know  when  the  exact  degree  of  hardness  is  reached. 
Knives  require  an  orange,  chisels  a  crimson,  springs 
and  swords  a  blue  tint.  Cheap  knives  made  of  cast- 
iron  are  often  covered  with  a  superficial  coating  of 
steel.  They  are  simply  heated  with  charcoal  a  little 
time,  so  that  the  outside  only  becomes  steelified,  as 
it  were.  When  we  use  such  knives,  we  soon  wear 
through  this  crust,  and  find  cast-iron  beneath,  which 
will  take  no  edge. 

Galvanized  Fe. — This  is  formed  by  dipping  sheets 
of  iron  in  melted  zinc,  a  thin  layer  of  which  adheres 
to  the  iron  and  prevents  oxydation. 

BISULPHURET  OF  FE  (Fe  82),  iron  pyrites— fool' s  gold  ; 
so  called,  because  it  is  often  mistaken  by  ignorant 
people  for  gold.  It  occurs  in  cubical  crystals  and 
bright  shiny  scales.  It  can  be  easily  tested  by  roast- 
ing it  on  a  hot  shovel,  when  we  will  catch  the  well- 
known  odor  of  the  S. 

SULPHATE  OF  FE  (FeO.SO3  +  7HO) — green  vitriol, 
copperas,  made  at  Stafford,  Connecticut,  from  FeS2, 
by  exposure  to  air  and  moisture.  It  is  formed  in  the 

enough  to  continue  the  operation.  When  the  iron  is  entirely 
decarbonized,  enough  iron,  rich  in  carbon,  called  "  spiegeleisen," 
or  "  looking-glass  iron,"  is  added  to  transform  it  into  steel.  At  the 
conclusion,  in  less  than  twenty  minutes  commonly,  the  entire  mass 
of  tons  weight  is  run  out  and  cast  into  bars  of  the  veiy  best  steel. 
This  method  lias  revolutionized  the  oM  modes  of  manufacture. 


ZINC. 


131 


same  manner  in  the  decay  of  rocks,  containing  iron 
pyrites,  and  is  found  in  the  soil  Used  in  dyeing, 
making  ink,  and  in  photography. 


ZINC. 

Symb.  Zn-..-Equiv.  32.5-. .-Spec.  Crav.  7- --Fusing  Point, 470°  F. 

Source. — Zinc,  or  "  spelter"  as  it  is  called  in  com- 
merce, is  found  in  ZnO,  or  red  oxyd,  in  New  Jersey, 
and  as  ZnS,  or  zinc  blende,  at  many  places. 

Preparation, — ZnO  is  purified  on  the  same  prin- 
ciple as  iron  ore,  by  heating  the 
powdered  ore  with  C.     The  re- 
action is  as  follows : 

ZnO  4-  0 


Zn     +  CO 

Both  these  products  distil  as 
a  vapor,  and  the  Zn  is  condensed 

while  GO  escapes.  _  Roasting  Zinc  Ore. 

Properties.— Ordinary  Zn  is  brittle,  but  singularly 
enough,  when  heated  to  200°  or  300°  F.,  it  becomes 
malleable,  and  is  rolled  out  into  the  sheet  Zn  in  use 
so  commonly.  It  burns  in  the  air  with  a  magnificent 
green  light,  forming  great  flakes  of  ZnO,  sometimes 
called  "  Philosopher's  Wool."  Example  :  On  a  red- 
hot  ladle  sprinkle  some  powdered  saltpetre  and  Zn 
filings.  The  KO.NO5  will  furnish  O,  and  the  metal 
will  burn  with  great  brilliancy.  When  exposed  to 


132  ELEMENTARY  CHEMISTRY. 

the  air,  Zn  soon  oxydizes,  and  the  thin  film  of  white 
oxyd,  formed  over  its  surface,  protects  it  from  further 
change. 

Uses. — It  has  many  economic  uses,  known  to  all. 
The  oxyd,  ZnO,  is  sold  as  zinc-white,  and  is  much 
valued  as  a  paint,  since  it  is  not  deleterious  to  the 
painters,  and  does  not  blacken  by  HS  like  white- 
lead.  The  sulphate,  ZnO .  SO3  (white  vitriol),  is  a 
powerful  emetic. 

T  IN. 
Symb.Sn....Equiv.  56. ...Spec.  Crav.  7.2- ...Fusing  Point,  420°  F. 

Sn  is  found  mainly  in  Cornwall,  England,  in 
Jackson,  New  Hampshire,  in  slight  quantities,  and 
in  Missouri.  It  is  not  ductile,  but  is  very  malleable, 
so  that  tinfoil  is  not  more  than  y^Vrr  of  an  incn  iQ 
thickness.  When  quickly  bent,  it  utters  a  shrill 
sound,  called  the  "  tin  cry,"  caused  by  the  crystals 
moving  upon  each  other.  The  tendency  of  Sn  to 
crystallize  is  remarkable.  Example:  Heat  a  piece 
of  Sn  till  the  coating  begins  to  melt;  then  cool 
quickly  and  clean  it  in  aqua-regia.  The  surface  will 
be  found  to  be  covered  with  beautiful  crystals  of 
the  metal.  Ordinary  tin-ware  is  formed  by  dipping 
sheet-iron  in  melted  Sn,  which  produces  an  artificial 
coating  of  the  latter  metal.  If  we  leave  HO  in  a  tin 
dish  long,  the  yellow  spots  betray  the  presence  of 
Fe.  Tin  does  not  oxydizo  at  ordinary  temperatures. 
Sn02,  sold  as  putty  poicder,  and  used  for  white 


COPPER.  133 

enamel  and  for  polishing  glass,  is  formed  by  the 
action  of  NO5  on  Sn.  Example  :  Pour  a  little  dilute 
NO5  on  scraps  of  tin,  and  watch  the  evolution  of 
nitrous  acid  fumes,  and  the  formation  of  SnO2. 
SnS2  is  the  ordinary  mosaic  gold  used  in  printing 
the  bronze  letters  and  figures  on  handbills  and 
wall-paper.  Pins  are  made  of  brass  wire,  and  then 
boiled  with  tin  and  cream  of  tartar.  This  gives 
a  bright  white  surface  to  the  metal.  The  pins  are 
stuck  in  papers,  as  we  see  them,  by  machinery 
which  picks  them  up  out  of  a  miscellaneous  pile, 
counts  them,  and  inserts  them  in  the  paper,  com- 
plete for  the  market.  The  first  part  of  the  process 
is  performed  by  a  sort  of  coarse  comb,  which  is 
thrust  into  the  heap,  and  gathers  up  a  pin  in  each 
of  the  spaces  between  the  teeth. 

COPPER. 
Symb.  Cu-..-Equiv.  31.7-.. -Spec.  Crav.  8.9-... Fusing  Pt.  1996°  F. 

Sources. — Found  native  near  Lake  Superior,  fre- 
quently in  masses  of  great  size.  In  these  mines  are 
discovered  stone  hammers,  the  tools  of  a  people 
more  ancient  than  the  Indians,  who  probably  occu- 
pied this  continent,  and  worked  the  mines.  In  the 
Western  mounds  copper  instruments  are  found. 
Malachite,  CuO .  CO2,  is  the  best  known  ore  of  copper. 
It  is  found  in  Siberia,  and  is  worked  into  beautiful 
ornaments,  much  prized  by  the  Russian  nobles. 
.  Properties.— It  is  ductile,  malleable,'  and  a  cpn- 


134  ELEMENTARY  CHEMISTRY. 

ductor  of  electricity.  Its  vapor  gives  a  characteristic 
and  beautiful  green  color  to  flame.  It  is  hardened 
by  hammering,  and  softened  by  heating  and  plung- 
ing into  cold  HO, — just  the  reverse  of  iron,  which 
fact  spoils  all  our  good  theories  as  to  the  cause  in 
either  case.  In  a  damp  atmosphere,  the  CO2  unites 
with  it,  forming  CuO.CO2,  familiarly  but  improperly 
called  verdigris.  The  true  verdigris  is  acetate  of  Cu  0, 
and  is  produced  when  we  soak  pickles  in  brass  or  cop- 
per kettles ;  the  green  color  which  results  is  simply  this 
salt — a  deadly  poison.  Preserved  fruits,  etc.,  should 
never  stand  in  such  vessels,  as  the  vegetable  acids 
dissolve  Cu  readily.  The  black  coating  which  col- 
lects on  copper  or  brass  kettles  is  the  black  oxyd  of 
copper,  CuO,  and  very  poisonous.  It  dissolves  readily 
in  fats  and  oils.  Such  utensils  should  therefore  be 
used  only  when  perfectly  bright,  and  then  never  with 
any  fruits,  sweetmeats,  jellies,  pickles,  etc.  Its  sol- 
vent is  NO5.  Its  test  is  NH3,  forming  in  a  solu- 
tion a  pale  blue  precipitate,  which  dissolves  in  an 
excess  of  the  reagent. 

SULPHATE  OF  COPPER  (CuO.SO3  -f  5HO)— Hue 
vitriol — is  much  used  in  dyeing,  calico  printing,  and 
galvanic  batteries. 

LEAD. 

Sym,,  Pb...-Equiv.,  I03.6...-Spec.  Gr.,  1 1,44-...  Fusing  Pt.,6l2°F. 

Sources. — It  is  found  almost  pure  in  cubical  crys- 
tals, but  its  most  common  ore  is  galeaa,  a  sulphuret 


LEAD.  135 

(PbS),  which  is  reduced  by  roasting  in  a  reverbera- 
tory  furnace.     The  S  burns  and  leaves  the  metal. 

Properties. — It  is  malleable,  but  contracts  as  it 
solidifies,  so  it  cannot  be  used  for  castings.  It  is  poi- 
sonous, though  not  immediately,  as  bullets  have  been 
swallowed,  and  then  thrown  off  without  any  harm 
except  the  fright.  Its  effects  seem  to  accumulate  in 
the  system,  and  finally  to  manifest  themselves  in 
some  disease.  Persons  who  use  lead,  as  painters 
and  plumbers,  after  a  time  suffer  with  colics,  paraly- 
sis, etc.  It  is  much  used  for  water-pipes,  and  is  the 
most  convenient  of  any  metal  for  that  purpose. 
Pure  water  passing  through  the  pipe  will  not  corrode 
the  lead,  but  the  O  of  the  air  it  contains  forms  an 
oxyd  of  lead  which  dissolves  in  the  HO.  If  there 
are  any  sulphates  or  carbonates  in  the  HO,  these 
will  form  a  coating  over  the  lead,  and  protect  it  from 
further  corrosion ;  and  as  carbonate  of  lime  is  com- 
mon in  all  hard  water,  that  is  safe.  If,  when  we  ex- 
amine a  lead  pipe  that  is  in  constant  use,  we  find  it 
covered  with  a  white  film,  that  is  a  good  sign ;  but 
if  it  is  bright,  there  is  cause  for  alarm.  Still,  how- 
ever much  may  be  said  upon  the  danger,  people  will 
use  lead  pipes,  and  the  following  precautions  should 
be  observed  :  Always  let  the  water  run  long  enough  in 
the  morning  before  using,  to  remove  all  which  has  re- 
mained in  tJie  water-pipes  during  tJie  night,  and  after 
the  HO  has  been  drawn  off  for  awhile,  when  it  is  let 
on  again,  leave  the  faucet  open  until  the  pipe  is  thor- 
oughly washed. 


136  ELEMENTARY   CHEMISTRY. 

OXYD  OF  LEAD  (PbO)  is  the  well-known  litharge, 
and  is  used  in  glass-making,  in  paints,  and  in  glaz- 
ing earthenware,  as  we  have  elsewhere  described. 

MINIUM,  or  red-lead  (Pb3O4),  is  used  for  coloring 
sealing-wax  red,  and  as  a  paint. 

CARBONATE  OF  LEAD  (PbO.CO2).—  White-Lead.— 
This  salt  is  made  in  large  quantities  in  the  following 
manner.  Thousands  of  earthen  pots  fitted  with 
covers  are  filled  with  weak  vinegar  (acetic 
acid)  and  a  small  roll  of  lead,  arranged  in 
immense  piles,  and  then  covered  with  tan- 
bark.  The  acetic  acid  combines  with  the 
lead,  but  the  CO2  formed  by  the  decom- 

A  —  An   earthen  t 

pL-Acoiionead  posing  tan-bark  creeps  in  under  the  cover, 
olu      of  driving  off  the  acetic  acid,  and  forming 


carbonate  of  lead.  The  acetic  acid,  thus  dispossessed, 
attacks  another  portion  of  the  lead,  but  is  robbed 
again  ;  and  so  the  process  goes  on,  until  at  last  all  the 
lead  is  exhausted.  White-lead  is  largely  adulterated 
with  sulphate  of  baryta  —  heavy  spar.  This  can  be 
easily  detected  by  digesting  (gently  heating)  a  little 
in  NO5,  or  even  in  strong  vinegar,  which  will  form  a 
soluble  nitrate  or  acetate  of  all  the  lead  in  the 
paint,  while  the  baryta  will  settle  to  the  bottom  as 
a  white  precipitate. 

ACETATE  OF  LEAD  (PbO.A)  —  Sugar  of  Lead.  —  This 
salt  has  a  sweet,  pleasant  taste,  and  has  been  fre- 
quently taken  by  mistake,  owing  to  its  being  in  such 
common  use.  It  is  a  virulent  poison.  The  antidote 
is  Epsom  salts,  which  forms  an  insoluble  sulphate 


ARSENIC.  137 

of  lead.  Water  dissolves  it  readily.  Ex. : 
If  a  piece  of  zinc,  cut  in  small  strips,  be 
suspended  in  a  bottle  filled  with  a  solution 
of  this  salt,  the  lead  will  be  deposited  upon 
it  by  voltaic  action  in  beautiful  metallic 
spangles,  forming  the  "lead-tree."  TheLeau-treo. 

Test  of  Pb.— This  is  HS,  which  forms  with  the 
metal  the  black  sulphuret  of  lead  (PbS).  A  very 
comical  illustration  is  as  follows  :  Thicken  a  solution 
of  PbO.A  with  a  little  gum-arabic,  so  as  not  to  flow 
too  readily  from  the  pen,  and  then  make  the  funniest 
drawing  of  which  you  can  conceive.  This,  when 
dry,  will  be  invisible.  When  it  is  to  be  used  dampen 
the  paper  slightly  on  the  wrong  side,  and  then  direct 
against  it  a  jet  of  HS,  and  the  picture  will  blacken 
into  beauty. 

ARSENIC. 

Symbol,  As ••••  Equivalent,  75- •••  Specific  Gravity,  5.8. 
Volatilizes  without  fusion  at  356°  F. 

This  is  a  brittle,  steel-gray  metal,  commonly  sold 
when  impure  as  Cobalt.  If  heated  in  the  open  air 
it  gives  off  the  odor  of  garlic,  which  is  a  test  of  As. 

ARSENIOUS  ACID  (As03). — This  is  the  well-known 
"  ratsbane,"  and  is  sometimes  sold  as  simply 
"  arsenic." 

Preparation. — It  is  made  in  Silesia,  by  roasting 
arsenical  iron  ore  at  the  bottom  of  a  tower,  above 
which  is  a  series  of  rooms  through  which  the  vapors 


138  ELEMENTARY   CHEMISTRY. 

ascend,  and  pass  out  through  a  chimney  at  the  top. 
The  As  bums,  forming  AsO3,  which  collects  as  a 
white  powder  on  the  walls  and  floors  of  the  cham- 
bers above.  Its  removal  is  a  work  of  great  danger. 
The  workmen  are  entirely  enveloped  in  a  leathern 
dress  and  mask  with  glass  eyes ;  they  breathe  through 
a  moistened  sponge,  thus  filtering  the  air  of  the  fine 
particles  of  arsenic  floating  through  it.  Yet,  in  spite 
of  all  these  precautions,  the  workmen  rarely  live 
beyond  forty. 

Properties. — Arsenious  acid  (arsenic)  is  soluble  in 
hot  HO,  and  has  a  slightly  sweetish  taste.  It  is  a 
powerful  poison,  doses  of  two  or  three  grains  being 
fatal,  although  an  over-dose  acts  as  an  emetic.  It 
is  an  antiseptic,  and  so  in  cases  of  poisoning  fre- 
quently attracts  attention  by  the  perfect  preservation 
of  the  body,  even  twenty  or  thirty  years  after  the 
murder  has  been  committed.  The  antidote  is  milk, 
whites  of  eggs,  or  s  as  ds  (t1  e  later  being  good  in 
almost  any  case  of  poisoning),  taken  immediately.  The 
exact  chemical  antidote  is  the  hydrated  sequioxyd 
of  iron,  prepared  by  adding  an  ;  Ikali  to  a  solution 
of  copperas  (FeO .  SO3).  The  bulky  precipitate  soon 
reddens  by  the  absorption  of  O  from  the  air,  and 
becomes  the  sesquioxyd.  It  must  be  perfectly  fresh 
and  moist  to  be  of  any  value. 

MARSH'S  TEST. — There  is  no  other  poison  which  is 
so  easily  detected.  Prepare  a  flask  for  the  evolution 
of  H.  Ignite  the  jet  of  gas,  and  hold  in  the  flame 
a  cold  porcelain  dish.  If  the  materials  contain  no 


AllSENIC. 


139 


As,  it  will  remain  untarnished.  Now  pour  in  through 
the  funnel-tube  a  few  drops  of  a  solution  of  As 
(made  by  dissolving  a  little  AsO3  in  HC1),  and  the 
color  of  the  flame  will  be  seen  to  change  almost  in- 
stantly, and  a  copious  "metallic  mirror"  of  As  will 
be  deposited  on  the  dish.  The  gas  formed  in  this 
experiment — arsenuretted  hydrogen — is  very  poison- 
ous indeed,  and  the  utmost  care  should  be  used  to 
prevent  its  inhalation.  In  a  case  of  poisoning,  of 


Marsh' 3  Tept. 

course,  the  contents  of  the  stomach  would  be  substi- 
tuted for  the  solution  of  As,  and  many  other  testa 
besides  this  would  be  employed.  "We  can  imagine 
with  what  care  a  chemist  would  conduct  this  test, 
and  with  what  intense  anxiety  he  would  watch  the 
porcelain  dish  as  the  flame  played  upon  it,  hesitating, 
and  dreading  the  issue,  as  he  felt  the  life  of  a  fellow- 
being  trembling  on  the  result  of  his  experiment. 
Arsenic-eating. — It  is  said  that  the  peasants  in 


140  ELEMENTARY  CHEMISTRY. 

portions  of  Hungary  are  accustomed  to  eat  As,  both 
fasting  and  as  a  seasoning  to  their  food.  A  very 
minute  portion  will  warm  and  stimulate  and  aid  in 
climbing  lofty  mountains.  The  arsenic-eaters  are 
described  as  plump  and  rosy,  and  it  is  said  that  the 
young  people  resort  to  it  as  a  species  of  cosmetic  to 
make  them  more  attractive.  They  begin  with  small 
doses,  which  are  gradually  increased  ;  but  if  the 
person  should  cease  the  practice  at  any  time,  all  the 
symptoms  of  arsenic  poisoning  immediately  appear. 
Horse-jockeys  are  said  to  feed  arsenic  to  their 
horses  to  improve  their  flesh  and  speed. 

CHROMIUM. 

Symbol,  Cr. 

This  element  is  commonly  known  as  combined 
with  O  in  chromic  acid,  CrO3.  The  ruby  owes  its 
beautiful  red  to  this  acid.  Bichromate  of  potassa, 
KO .  2CrO3,  is  a  red  salt,  much  used  in  the  laboratory, 
dyeing,  etc.  Example  :  If  we  mix  a  solution  of  this 
salt  and  one  of  sugar  of  lead,  a  yellow-colored  pre- 
cipitate will  be  formed,  known  as  chrome  yellow 
(PbO .  CrO3),  valued  in  painting  and  dyeing.  Ex. : 
Moisten  a  piece  of  flannel  in  a  solution  of  sugar  of 
lead  (PbO.  A),  then  in  one  of  Glauber's  Salts  (NaO. 
SO3),  to  change  the  acetate  of  lead  to  a  sulphate  of 
lead,  and  lastly,  in  one  of  bichromate  of  potash, 
when  the  cloth  will  be  found  to  be  dyed  a  per- 
manent yellow. 


MERCURY. 


THE  NOBLE  METALS. 

These  are :  Mercury,  Silver,  Gold,  Platinum, 
Palladium,  Iridium,  Osmium,  Ruthenium,  Rhodium. 

MERCURY. 

Symbol,  Hg---- Equivalent,  100- •• -Specific  Gravity,  13.5. 
Freezes  at  -39°  F-... Boils  at  662?  F. 

Mercury  is  also  called  quicksilver,  because  it  runs 
about  as  if  it  were  alive,  and  was  supposed  by  the 
alchemists  to  contain  silver.  It  was  known  very 
anciently,  and  the  mines  of  Spain  were  worked  by 
the  Romans. 

Source. — Cinnabar,  HgS,  a  brilliant  red  ore,  called 
also  "vermilion,"  is  the  principal  source  of  this 
metal.  It  is  found  native  in  Mexico  in  very  small 
quantities,  where  the  mines  are  said  to  have  been 
discovered  by  a  slave,  who,  in  climbing  a  mountain, 
came  to  a  very  steep  ascent.  To  aid  him  in  sur- 
mounting this,  he  tried  to  draw  himself  up  by  a  bush 
which  grew  in  a  crevice  above.  The  shrub,  however, 
giving  way,  was  torn  up  by  the  roots,  and  a  tiny 
stream,  of  what  to  him  seemed  liquid  silver,  trickled 
down  upon  him. 

Properties. — Mercury  emits  a  vapor  at  all  temper- 
atures above  40°  F.  Its  solvent  is  NO5.  It  is  the 
only  element,  except  bromine,  that  is  fluid  at  ordi- 
nary temperatures.  It  forms  an  amalgam — a  union 


142  ELEMENTARY  CHEMISTRY. 

of  Hg  and  a  metal — viz.,  gold  or  silver.  We  should 
therefore  never  touch  a  gold  ring,  for  instance,  to 
Hg,  as  it  will  cover  it  immediately  with  a  thin  film 
of  this  amalgam. 

Uses. — Hg  is  extensively  employed  in  the  manufac- 
ture of  thermometers,  barometers,  for  silvering  mir- 
rors, and  extracting  the  precious  metals  from  their 
ores.  The  well-known  Uue-pill  is  Hg  incorporated 
with  chalk  and  flavored  with  liquorice.  Mercurial 
ointment,  "  anguintum,"  is  Hg  and  lard  well  rubbed 
together.  This  is  chiefly  employed  as  an  unguent 
for  domestic  use,  and  in  very  populous  schools.  Hg 
is  extensively  employed  in  medicine,  as  calomel, 
Hg2 .  Cl,  a  subchloride  of  mercury.  This  can  be  dis- 
tinguished from  any  other  substance  for  which  it  is 
liable  to  be  mistaken,  especially  corrosive  sublimate, 
from  the  fact  that  it  is  insoluble  in  HO,  and  perfectly 
tasteless.  The  action  of  Hg  on  the  human  system 
is  too  well  known  to  need  description.  "  In  its  me- 
tallic state,  Hg  has  been  taken  with  impunity  in 
quantities  of  a  pound  weight"  (Am.  Cyc.},  but  when 
finely  divided,  as  in  vapor  or  "blue-pill,"  its  effects 
are  marked.  It  renders  the  patient  extremely  sus- 
ceptible to  colds,  acts  directly  upon  the  liver,  in- 
creasing the  secretion  of  bile,  and  in  over-doses 
produces  "  salivation." 

BED  OXYD  OF  Hg,  "red  precipitate,"  is  interesting, 
as  the  substance  from  which  Priestley  discovered 
O  gas. 

CHLORIDE  OF  Hg  (Hg.Cl),  "  corrosive  sublimate,"  is 


MERCURY.  143 

well  known  to  housekeepers.  It  is  a  heavy,  white 
solid,  soluble  in  HO,  and  with  a  burning  metallic 
taste.  It  has  powerful  antiseptic  properties,  and  is 
used  to  preserve  specimens  in  natural  history.  It  is 
a  deadly  poison,  and  its  antidote  is  white  of  eggs, 
milk,  etc. 

Mirrors  were  anciently  made  of  steel  or  silver, 
highly  polished.  They  were  very  liable  to  rust  and 
tarnish,  and  so  a  piece  of  sponge,  sprinkled  with  pum- 
ice-stone, was  suspended  from  the  handle  for  rubbing 
the  mirror  before  use.  Seneca,  in  lamenting  over 
the  extravagance  of  his  day  among  the  old  Romans, 
says :  "  Every  young  woman  now-a-days  must  have 
a  silver  mirror."  The  process  of  silvering  ordinary 
mirrors  is  as  follows.  Tinfoil  is  first  spread  evenly 
over  the  glass,  and  then  the  Hg  is  carefully  poured 
over  it.  The  two  metals  combine,  forming  a  bright 
amalgam,  which  clings  to  the  glass.  The  superfluous 
Hg  is  cautiously  wiped  or  pressed  off.  When  we 
look  into  a  mirror  we  rarely  realize  what  it  has 
cost  others  to  thus  minister  to  our  comfort.  The 
workmen  are  short-lived.  A  paralysis  sometimes 
attacks  them  within  a  few  weeks  after  they  enter  the 
manufactory,  and  it  is  thought  remarkable  if  a  man 
escapes  for  a  year  or  two.  Its  effects  are  similar  to 
those  we  have  just  spoken  of  when  treating  of  calo- 
mel ;  the  patient  dances  instead  of  walks,  he  cannot 
direct  the  motion  of  his  arms,  nor  in  some  cases 
even  masticate  his  food. 


144  ELEMENTAEY  CHEMISTRY. 

IKIDIUM. 

Symbol,  Ir-..- Equivalent,  99  ••••  Specific  Gravity,  21.15. 

This  metal  is  named  from  Iris,  the  rainbow,  be- 
cause of  the  beautiful  color  of  its  salts  in  solution. 
It  is  the  heaviest  of  the  elements,  being  over  21  times 
as  heavy  as  water.  When  combined  with  Osmium,  it 
makes  "  irodosmine,"  well  known  as  the  points  of 
gold  pens. 

PLATINUM. 

Symbol,  Ft-.-.  Equivalent,  98-6-.. .  Specific  Gravity,  21.5 
Fusing  Point,  4591°  F. 

Source. — Platinum  is  chiefly  found  in  the  Ural 
Mountains,  where  it  occurs  in  alluvial  deposits,  in 
small,  flattened  grains. 

Properties. — It  resembles  Ag  in  its  appearance. 
It  is  the  most  ductile  metal  known,  wire  having  been 
made  from  it  so  fine  as  to  be  invisible  to  the  naked 
eye.*  It  is  soluble  in  aqua-regia,  but  not  in  the 
simple  acids.  It  does  not  oxydize  in  the  air,  is  the 
most  infusible  of  substances,  and  can  be  melted  only 

*  Wollaston's  Method,  as  it  is  called,  consists  in  covering  fine 
platinum  wire  with  several  times  its  weight  of  silver,  and  then 
drawing  this  through  the  plates  used  for  drawing  wire  until  the 
finest  hole  is  reached,  when  the  wire  is  placed  hi  NO6,  which  dis- 
solves the  Ag  and  leaves  the  Pt  intact.  This,  in  the  form  of  the 
finest  wire  known,  may  be  found  in  the  solution  by  means  of  a 
microscope.  A  single  ounce  of  Pt,  it  is  said,  will  make  a  wire 
that  would  reach  from  New  York  to  New  Orleans. 


GOLD.  145 

by  the  heat  of  the  compound  blow-pipe  or  voltaic 
battery.  In  the  arts  it  is  fused  in  the  former  man- 
ner. These  properties  fit  it  for  use  as  crucibles  in 
the  laboratory,  and  for  this  purpose  it  is  invaluable 
to  the  chemist. 

GOLD. 

Symbol,  Au  . . . .  Equivalent,  196.4 ....  Specific  Gravity,  19.34. 
Fusing  Point,  2016°  F. 

Sources. — Gold  is  widely  diffused.  It  occurs  some- 
times in  cubes,  in  masses  called  nuggets,  and  is 
always  native.  It  is  found  generally  in  small  grains, 
or  scales,  scattered  through  the  rocks.  As  these 
disintegrate  by  the  action  of  the  elements,  the  gold 
is  gradually  washed  into  the  valleys  below,  and 
thence  into  the  streams  and  rivers,  where,  owing  to 
its  specific  gravity,  it  settles  and  collects  in  the  mud 
and  gravel  of  their  beds.  In  this  way  we  trace  the 
origin  of  the  extensive  gold-plains  of  California. 

Preparation. — As  the  metal  is  thus  found  native, 
the  process  is  purely  mechanical,  and  consists  simply 
in  washing  out  the  dirt  and  gravel  in  wash-pans, 
rockers,  etc.,  at  the  bottom  of  which  the  metal  ac- 
cumulates, the  only  requisites  being  these  tools  and 
an  abundance  of  water.  In  the  quartz-mills  the  rock 
is  thrown  into  great  troughs  of  water,  in  which,  by 
heavy  stamps,  the  ore  is  crushed  to  powder.  As  the 
thin  liquid  mud  thus  formed  splashes  up  on  either 
side,  or  is  conducted  from  the  stamping-mill,  it  runs 

7 


146  ELEMENTAKY  CHEMISTRY. 

over  broad  metallic  tables  covered  with  mercury. 
This  unites  with  the  little  particles  of  gold  as  they 
are  washed  along,  and  forms  with  them  an  amalgam 
(a  compound  of  mercury  and  a  metal).  From  this 
the  gold  is  easily  separated  by  distillation,  and  the 
mercury  collected  to  be  used  again. 

QUARTATION.  —  Gold  is  sometimes  alloyed  with  sil- 
ver. In  that  case  the  silver  is  dissolved  out  by  NO5. 
There  must  be  three  parts  of  silver  to  one  of  gold, 
else  the  gold  will  protect  all  the  silver  from  the 
action  of  the  acid.  If  there  is  not  so  much,  some 
is  added. 

Properties.  —  Pure  ore  is  nearly  as  soft  as  lead.  It 
is  extremely  malleable  and  ductile.  Its  solvent  is 
aqua-regia.  It  does  not  oxydize  at  any  temperature. 

GOLD-LEAF.  —  The  process  of  making  gold-leaf  is 
very  simple.  The  metal  is  first  rolled  into  thin  rib- 
bon, and  then  divided  into  pieces  one  inch  square. 
These  are  placed,  one  by  one,  between  leaves  of 
gold-beaters'  skin  and  hammered  until  they  are 
beaten  four  inches  square,  when  they  are  subdivided 
into  four  pieces,  each  one  inch  square.  These  are 
hammered  as  before,  and  the  process  repeated  until 
the  required  thinness  is  obtained. 


Symb.,Ag....Equiv.f  I08-.  ..Spec.  Or.,  10.5...  -Fusing  Pt.,  1873"  F, 

Sources.  —  Silver  is   found  throughout    tie   great 
West  in  a  distracting  variety  of  forms—  most  ccm- 


SILVER.  147 

monly,  however,  combined  with  S,  as  black  sulphur  et, 
AgS ;  with  Cl,  forming  horn-silver,  AgCl ;  with  As, 
making  ruby-silver,  AgAs,  and  also  associated  with 
lead  in  ordinary  galena. 

Preparation. — 1st.  The  sulphuret  is  refined  as  fol- 
lows. The  ore  is  crushed  into  fine  powder  and  then 
roasted  with  common  salt.  The  Cl  of  the  salt  unites 
with  the  Ag,  forming  chloride  of  silver,  AgCl.  This 
is  now  put  into  a  revolving  cylinder  with  HO,  Hg, 
and  iron-scraps.  The  iron  takes  the  Cl  away  from 
the  silver,  and  the  Hg  catches  it  up,  thus  forming 
an  amalgam  of  Hg  and  Ag.  From  this  the  silver  is 
easily  obtained,  as  in  gold-washing.  2d.  From 
horn-silver,  AgCl,  the  process  is  like  the  latter  part 
of  that  we  have  just  described.  3d.  From  lead  the 
silver  can  be  profitably  obtained  even  when  there  is 
not  more  than  ten  ounces  in  a  ton.  The  aUoy  of  the 
two  metals  is  melted  and  then  slowly  cooled.  Lead 
solidifies  much  sooner  than  silver,  and  by  skimming 
out  the  crystals  of  Pb  as  fast  as  formed,  they  may 
be  almost  entirely  separated. 

Cupellation. — A  cupel  is  a  shallow  vessel,  made  of 
bone-ashes.  In  this  the  silver,  debased  with  lead 
and  other  impurities,  is  placed  and 
exposed  to  a  red  heat,  so  as  to  melt 
the  metals,  while  a  current  of  hot  air 
plays  upon  the  surface.  The  lead  A  c»i)Cl- 
oxydizes,  is  changed  to  litharge,  PbO,  and  is  ab- 
sorbed by  the  porous  cupel.  The  mass  appears 
soiled  and  tarnished,  but  the  refiner  keeps  his  eye 


148 


ELEMENTARY  CHEMISTRY. 


upon  it  as  the  process  continues,  watching  eagerly, 
until  at  last  there  is  a  brilliant  play  of  colors — he 
catches  his  own  image  in  the  perfect  metallic  mirror, 
and  the  little  "  button"  of  pure  silver  lies  gleaming 
at  the  bottom.*  This  must  now  be  immediately  re- 
moved, or  it  will  oxydize  and  waste. 


Cupels  in  Furnace. 

Properties. — Silver  is  the  whitest  of  all  the  metals. 
It  is  malleable  and  ductile.  It  expands  at  the  mo- 
ment it  solidifies,  and,  therefore,  can  be  cast.  It 
has  a  powerful  attraction  for  sulphur,  forming  the 
black  sulphuret  of  silver.  The  perspiration  from 
our  bodies  contains  more  or  less  S,  and  this,  as  it 

*  Malachi,  ill  3. 


SILVER.  149 

passes  through  our  pockets,  fraternizes  with  any  sil- 
ver we  may  chance  to  have  there.  Silver  spoons 
and  door-knobs  are  tarnished  by  the  minute  quan- 
tity of  HS  present  in  the  air.  Those  who  have 
visited  any  sulphur  springs  know  the  propriety  of 
carefully  protecting  their  gold  or  silver  watches,  and 
of  never  carrying  them  to  the  hot  baths.  AgS  is 
very  easily  dissolved  by  a  little  dilute  ammonia  (1 
part  of  NH3  to  10  of  HO),  which  is  therefore  used 
for  cleaning  silver  door-knobs.  The  solvent  of  Ag 
is  NO5.  The  test  of  silver  in  solution  is  HC1,  which 
forms  a  cloudy  precipitate  of  chloride  of  silver,  AgCl. 
A  solution  of  silver  coin  is  blue,  from  the  copper  it 
contains. 

NITRATE  OF  SILVER  (AgO.NO5). — It  is  sold  in  crys- 
tals, and  also  in  sticks  as  lunar  caustic.  It  js  used 
as  a  cautery.  It  stains  the  skin  and  all  organic  mat- 
ter black,  owing  to  its  decomposition  by  the  light 
and  the  formation  of  oxyd  of  silver,  AgO.  A  very 
pretty  experiment,  illustrating  this,  is  performed  by 
dropping  into  a  test-tube  of  HO  a  few  drops  of 
nitrate  of  silver  in  solution,  and  then  adding  KO  : 
a  copious  precipitate  of  AgO  will  fill  the  tube.  At 
last  add  a  little  NH3,  and  it  will  instantly  dissolve 
the  black  oxyd,  and  leave  the  solution  as  clear  and 
sparkling  as  spring-water.  The  stain  from  nitrate 
of  silver  may  be  removed  by  a  solution  of  cyanide 
of  potassium.  Hair-dyes  and  indelible  inks  consist 
mainly  of  this  salt  of  silver. 


150  ELEMENTARY  CHEMISTRY. 

THE  ALLOYS. 

These  are  very  numerous,  and  many  of  them 
possess  properties  so  different  from  their  elements 
that  they  almost  seem  like  new  metals.  Their  color 
and  hardness  are  changed,  and  sometimes  the  melt- 
ing point  is  below  that  of  any  one  of  the  con- 
stituents. 

Type  Meted  contains  3  parts  lead  to  1  of  antimony. 

Britannia  consists  of  100  parts  tin,  8  antimony, 
2  bismuth,  and  2  of  copper. 

Brass  is  4  parts  of  copper  and  3  of  zinc. 

German  Silver  contains  copper,  zinc,  and  nickel — 
(brass  whitened  by  nickel). 

Soft  Solder,  used  by  tinsmiths,  is  made  by  melting 
lead  and  tin  together,  the  orthodox  proportion — half 
and  half.  Before  putting  on  the  solder,  they  moisten 
the  surface  of  the  metal  with  HC1,  which  dissolves 
the  coating  of  the  oxyd. 

Hard  Solder  is  composed  of  copper  and  zinc. 

Fusible  Metal  melts  at  203°,  and  spoons  made  of  it 
will  fuse  in  hot  tea.  It  can  be  melted  in  a  paper 
crucible  over  a  candle.  It  consists  of  bismuth,  lead, 
and  tin.  Yet  the  first  metal  melts  at  476°,  the  second 
at  600°,  and  the  third  at  442°. 

Bronze  is  90  parts  copper  and  10  of  tin. 

Gold  is  soldered  with  an  alloy  of  itself  and  silver ; 
Silver,  with  itself  and  copper ;  Copper,  with  itself  and 
zinc  :  the  principle  being  that  the  metal  of  lower 
fusing  point  causes  the  other  to  melt  more  easily. 


THE  ALLOYS.  151 

COIN. — The  precious  metals,  when  pure,  are  too 
soft  for  common  use.  They  are  therefore  hardened 
by  other  metals.  Gold  coin  consists  of  9  parts  gold 
and  1  of  alloy.  The  alloy  is  composed  of  9  parts  of 
copper,  whitened  by  one  of  silver,  so  as  not  to  darken 
the  gold  coin.  Silver  coin  is  9  parts  silver  and  1  of 
copper.  The  nickel  cent  is  88  parts  copper  and  12 
of  nickel.  The  object  of  the  copper  is  to  make  the 
coin  larger,  as  it  is  cheaper  than  nickel.  The  term 
carat,  applied  to  the  precious  metals,  means  -Jf  part. 
Therefore,  gold  18  carats  fine,  contains  Jf  of  gold 
and  26¥  of  alloy. 

SHOT  is  an  alloy  of  about  1  part  arsenic  to  100  of 
lead.  The  manufacture  is  carried  on  in  what  are 
called  "  shot-towers,"  some  of  which  are  two  hundred 
and  fifty  feet  high.  The  alloy  is  melted  at  the  top 
of  the  building,  and  poured  through  colanders. 
The  metal,  in  falling  so  far,  breaks  up  into  drops, 
which  take  the  "  spheroidal  form,"  harden,  and  are 
caught  at  the  bottom  in  a  well  of  water,  which  cools 
the  shot  and  also  prevents  their  being  bruised  in 
striking.  The  shot  are  dipped  out,  dried,  and  then 
assorted,  by  sifting  in  a  revolving  cylinder,  which  is 
set  slightly  inclined  and  is  perforated  with  holes,  in- 
creasing in  size  from  the  top  to  the  bottom.  The 
shot  being  poured  in  at  the  top,  the  small  ones  drop 
through  first,  next  the  larger,  and  so  on,  till  the 
largest  reach  the  very  bottom.  Each  size  is  received 
in  its  own  box.  Shot  are  polished  by  being  agi- 
tated for  several  hours  with  black-lead,  in  a  rapidly 


152  ELEMENTARY  CHEMISTRY. 

revolving  wheel.  The  shot  are  finally  tested  by 
rolling  them  all  down  a  series  of  inclined  planes 
placed  at  a  little  distance  from  each  other.  The 
spherical  shot  will  jump  from  one  plane  to  the  next, 
while  the  imperfect  ones  will  fall  short,  and  drop 
below ;  or  sometimes,  by  rolling  down  a  single  in- 
clined plane,  the  spherical  ones  will  go  to  the  bot- 
tom, while  the  imperfect  ones  roll  off  at  the  sides. 

OREIDE — a  beautiful  alloy,  resembling  gold — is 
made  at  Waterbury,  Connecticut.  It  is  a  French 
discovery.  It  consists  of  100  parts  copper,  tin  17 
parts,  magnesia  6  parts,  sal-ammoniac  3.6  parts,  lime 
1.8  parts,  cream  of  tartar  9  parts.  It  can  be  beaten 
into  leaves,  cast,  chased,  rolled,  and  stamped  like 
gold,  while  none  but  the  most  experienced  judges  can 
detect  the  difference. 

ALUMINUM  alloys  with  copper  are  becoming  valu- 
able, as  Al  is  itself  better  known.  They  are  elastic, 
malleable,  and  very  light. 


ORGANIC  CHEMISTRY. 


INTRODUCTION. 

WE  have  thus  far  spoken  of  the  various  elements 
of  matter.  We  have  found  "  dead,  mineral  matter," 
as  we  commonly  call  it,  all  alive  with  desire  and 
power.  Each  tiny  atom  has  revealed  to  us  a  force 
that  repelled  it  here,  attracted  it  there,  and  held 
it  to  its  place  as  with  bands  of  iron.  We  have 
traced,  through  all  the  varied  changes  of  matter,  the 
workings  of  one  law  and  one  system,  and  have  every- 
where discovered  our  comfort  and  happiness  to  be 
the  final  end  of  creation.  We  have  found  the  nicest 
cutting  and  planning,  whereby  each  element  appears 
fitted  to  its  place  in  nature,  as  a  skilful  mechanic 
adapts  one  cog  to  another  through  a  great  series  of 
machinery.  No  particle  of  matter  seems  left  to 
itself,  but,  watched  by  the  Eternal  Eye  and  guided 
by  the  Eternal  Hand,  obeys  immutable  law.  When 
Christ  declared  the  very  hairs  of  our  head  to  be 
numbered,  he  intimated  a  chemical  truth,  which  we 
can  now  know  in  full  to  be,  that  the  very  atoms  of 


154  ELEMENTARY  CHEMISTRY. 

which  each  hair  is  composed  are  all  numbered  by 
that  same  watchful  Providence. 

We  have  found  the  elements  of  the  growth  of  our 
bodies,  but  still  we  cannot  live  upon  them.  We  need 
phosphorus,  but  we  cannot  eat  it ;  it  would  burn 
us  to  a  coal.  We  need  iron,  but  it  would  make  a 
most  unsavory  diet.  We  need  lime,  but  it  would 
corrode  our  flesh.  We  need  H,  but  it  must  be  com- 
bined with  O  as  HO  to  be  of  any  value  to  us.  If 
we  were  shut  up  in  a  room  with  all  the  elements  of 
nature,  we  not  only  could  not  combine  them  so  as  to 
produce  any  of  those  organic  substances  necessary 
to  our  life  and  comfort,  but  we  would  actually  die 
of  starvation.  We  thus  see  that  the  mineral  matter 
must  be  assimilated  in  some  manner  before  we  can 
use  it  to  advantage.  Here  appears  the  object  of 
the  vegetable  world.  It  turns  inorganic  matter  into 
organic.  The  plant  taking  those  elements  which  we 
need  for  our  growth  and  for  use  in  the  arts  and 
sciences,  combines  them  into  plant  products,  such  as 
wood,  starch,  sugar,  coal,  etc. :  we  using  these,  live, 
grow,  and  develop  into  civilized  man,  fitted  for  all 
the  grand  achievements  of  life. 

How  strange  it  is  that  we  are  thus  dependent  upon 
plants!  We  know  they  decompose  the  poisonous 
CO2,  and  give  us  our  supply  of  the  inspiring  O,  but 
that  is  only  a  part  of  our  demands ;  they  furnish  us 
with  all  the  grand  staples  of  commerce,  of  luxury- 
all  we  eat,  or  drink,  or  wear.  Each  tiny  leaf  we  see, 
each  spire  of  grass  is  thus  incessantly  working 


INTRODUCTION.  155 

throughout  the  livelong  day  to  meet  our  constant 
wants. 

The  object  of  ORGANIC  CHEMISTRY  is  to  treat  of 
these  plant-products  and  the  various  substances  de- 
rived from  them.  Organic  bodies  differ  from  inor- 
ganic in  several  points. 

1st.  While  inorganic  bodies  deal  with  65  elements, 
organic  are  composed  principally  of  only  four,  C,  H, 
O,  N  —  which  are  therefore  called  "  ORGANOGENS"  — 
and  a  very  little  mineral  matter  constituting  the 
ash. 

2d.  While  inorganic  bodies  consist  of  only  a  few 
atoms,  and  are  therefore  very  simple  in  their  con- 
struction (Ex.  :  HO,  CO2,  KO),  organic  contain  a 
large  number,  and  are  extremely  complex.  Ex.  : 
Sugar  =C12H12O12  ;  Oil  of  cedar  =  C^H^Oz'y  Fibrine  = 


3d.  While  inorganic  bodies  are  formed  and  remain 
fixed  in  one  state  under  the  influence  of  chemical 
affinity,  organic  grow  rapidly,  change  constantly,  and 
when  life  ceases,  as  rapidly  decay,  and  are  trans- 
formed into  inorganic  substances. 

4th.  Owing  to  their  complex  structure,  and  the 
presence  in  very  many  of  the  negative  N,  they  form 
most  unstable  compounds.  In  this  we  see  the  reason 
of  their  rapid  decay.  The  vital  principle  alone  holds 
them  together,  frequently  in  opposition  to  the  laws 
of  chemical  affinity  ;  and  the  instant  that  is  removed, 
the  tendency  is  to  seek  new  affinities  and  form  new 
compounds. 

7* 


f 
156  ELEMENTARY  CHEMISTEY. 

NUMBER  OF  ORGANIC  BODIES. — This  is  almost  end- 
less, and  yet  is  constantly  increasing.  The  labor  of 
modern  chemists  is  largely  devoted  to  this  subject, 
and  the  field  opens  and  broadens  with  every  dis- 
covery. The  methods  of  classification  are  unsettled, 
and  new  and  conflicting  theories  yet  contend  on  this 
border-ground  of  chemical  knowledge.  Various  or- 
ganic bodies  are  now  formed  artificially  by  the  skill 
of  the  chemist,  and  many  others  are  broken  up  into 
simpler  forms.  Ex. :  Alcohol  =  water  and  carburet- 
ted  hydrogen. 

ISOMERISM. — Isomeric  compounds  are  those  that 
consist  of  the  same  elements  in  the  same  proportion. 
Ex. :  Heavy  carburetted  hydrogen,  petroleum,  oil  of 
roses,  and  caoutchouc,  consist  alike  of  C4H4.  So 
that  the  fragrant  odor  of  a  rose,  and  that  which 
comes  from  a  petroleum  lamp,  contain  precisely  the 
same  elements.  Isomerism  is  supposed  to  be  caused 
by  a  different  grouping  of  the  atoms  about  each 
other,  as  the  same  pieces  upon  a  checker-board  may 
be  differently  arranged. 

ALLOTROPISM. — Not  only  may  the  same  elements  be 
thus  differently  grouped,  and  produce  different  com- 
pounds, as  p-l-e-a  may  spell  also  1-e-a-p,  or  p-e-a-1, 
or  p-a-l-e,  but  also  the  individual  elements  are  sus- 
ceptible of  allotropic  states ;  as,  for  instance,  the  C 
in  a  compound  may  be  in  any  one  of  its  three  allo- 
tropic forms.  These  two  principles  of  isomerism 
and  allotropism  run  through  organic  chemistry,  and 


STARCH. 


157 


readily  account  for  the  inexhaustible  variety  of  its 
compounds.* 

STARCH  (C12H10Oi0). 

Source. — Plants  accumulate  it  in  their  roots — Ex., 
Carrot,  turnip :  in  subterranean  stems — Ex.,  Pota- 
toes, of  which  it  forms  20  per  cent. :  in  the  base  of 
leaves — Ex.,  Onion:  in  the  seed — Ex.,  Corn,  of 
which  it  forms  80  per  cent:  in  the  embryo — Ex., 
Bean,  pea.  In  all  these  it  is  stored  up  for  the  future 
growth  of  the  plant 
or  the  seed.  It  is  kept 
in  its  starch  form 
(lest  it  dissolve  in 
the  first  rain),  and 
then  turned  to  sugar 
only  when  and  as  the 
plant  needs  it  in 
growing.  The  ac- 
companying figures 
show  the  form  of  the 
i  ra'n  of  starch  in  a 
potato,  as  seen  under  the  microscope,  each  veg  tab'o 
having  its  peculiar  shape,  so  that  in  this  way  any 
adulteration  is  easily  detected. 

Preparation. — It  is  .made  from  wheat,  corn,  pota- 
toes. The  process  is  essentially  the  same  in  all. 
The  potato,  for  example,  is  ground  to  a  pulp,  and 


Starch  Grain. 


*  See  ORGANIC  CHEMISTRY,  in  Appendix. 


158  ELEMENTARY  CHEMISTRY. 

then  washed  with  cold  water.     The  starch  settles 
from  this  milky  mass  as  a  fine  white  precipitate. 


Properties. — It  is  insoluble  in  cold  water.  If 
heated  it  absorbs  water,  swells,  and  the  starch 
granules  burst,  forming  a  jelly-like  liquid,  used  for 
what  is  known  as  starching.  The  swelling  of  rice, 
beans,  etc.,  when  cooked,  is  owing  to  this  property. 
By  heat,  starch  undergoes  a  peculiar  change  into  a 
substance  known  as  dextrine,  or  British  gum,  used 
for  making  envelopes,  wall-paper,  "fig-paste,"  and  for 
stiffening  chintzes.  The  test  of  starch  is  iodine,  which 
forms  in  solution  a  beautiful  blue  iodide  of  starch. 
Sago  is  the  starch  from  the  pith  of  the  palm-tree ; 
tapioca  and  arrow-root  are  made  from  the  roots  of 
South  American  marshy  plants.  Very  many  of  the 
farinaceous  preparations  sold  for  the  sick  and  invalid, 
under  high-sounding  names,  are  simply  wheat  or 
corn  starch,  put  up  in  fancy  papers  and  gilt  lettering. 

GUM  (C12H10O10). — This  includes  a  variety  of  sub- 
stances which  exude  from  the  bark  of  trees.  Ex. : 
Cherry,  plum.  Gum-arabic  is  derived  from  an  Aca- 
cia tree.  . 


STARCH.  159 

PECTIC  ACID,  OR  PECTINE. — This  is  a  variety  of 
gum  existing  in  certain  fruits,  as  the  currant,  apple, 
etc.,  which  forms  the  vegetable  jelly  so  much  used 
as  a  sweetmeat.  In  the  fully  ripened  fruit,  this  turns 
to  sugar,  and  hence,  as  every  housewife  knows,  a 
jelly  cannot  be  made  from  the  fruit  except  at  a  cer- 
tain stage  in  the  ripening  process. 

CELLULOSE,  LIGNINE,  ETC.  (Ci2H10O10). — Woody  fibre 
is  found  in  various  modifications — in  the  heart  of  a 
tree,  in  shells  of  nuts,  and  stones  of  fruits.  Its  cells, 
filled  with  lignin,  are  hard  and  compact ;  in  the  sap- 
wood,  its  cells,  open  and  full  only  of  sap,  are  soft  and 
porous;  in  elder-pith  and  cork,  they  are  light;  in 
flax  and  cotton,  pliable ;  in  the  bran  of  wheat  and 
corn,  very  digestible.  It  composes  the  cells  of  ah1 
plants,  giving  them  strength  and  firmness,  and  is 
found  even  in  delicate  fruits,  holding  their  luscious 
juices. 

Secretion. — All  vegetation  consists  of  these  simple 
cells.  They  seem  alike  to  the  eye,  yet  they  have  a  won- 
derful power  of  secretion.  The  cell  of  the  sugar- 
maple  converts  the  sap  into  sugar — the  milk-weed, 
into  a  milky  juice — the  caoutchouc,  into  rubber ;  the 
pie-plant  manufactures  oxalic  acid,  and  the  rose-petal 
the  most  delicate  of  perfumes.  Then  again  they  are 
true  to  themselves.  There  seems  to  be  a  law  of  God 
stamped  on  each  cell,  so  that  when  we  cut  a  tiny  bud 
from  a  tree  and  graft  it  into  another,  it  remains  con- 
sistent with  itself.  It  develops  into  a  limb,  and  years 
pass  by — the  few  single  cells  become  a  myriad,  yet 


160  ELEMENTARY   CHEMISTRY. 

they  have  changed  not.  The  sap  flows  upward  in 
the  tree ;  but  at  a  certain  point — a  hidden  threshold 
which  no  human  eye  can  discern — it  comes  under  a 
new  and  strange  influence.  It  is  here  transformed, 
and  produces  fruit  and  flowers,  in  accordance  with 
this  new  law.  Somehow  quince-juice  is  made  into 
pears,  locust-juice  blooms  out  into  fragrant  acacias, 
while  sweet  apples  and  sour  apples  hang  "cheek- 
by-jowl"  on  the  same  limb. 

Uses. — These  are  wonderfully  various.  Woody  fibre 
is  woven  into  cloth,  built  into  houses,  -twisted  into 
rope,  twine,  and  thread,  cut  into  fuel,  carved  into 
furniture.  We  eat  it,  wear  it,  walk  on  it,  write  on  it, 
sit  on  it,  print  on  it,  pack  our  clothes  in  it,  sleep  in 
it,  ride  in  it,  and  burn  it. 

Curious  Discovery. — It  has  lately  been  found  that, 
by  feeding  the  roots  of  a  tree  with  some  coloring 
matter,  the  wood  of  the  trunk  may  be  stained  to 
imitate  any  color  desired.  In  this  way,  common 
pine  or  maple  takes  the  appearance  of  the  rarest 
wood — mahogany,  rosewood,  etc. 

PAPER  is  made  from  rags  of  all  kinds,  straw,  or 
indeed  almost  any  substance  containing  cellular 
tissue.  The  finest  writing-paper  is  manufactured 
from  the  best  of  linen  rags,  brought  from  Italy. 
The  rags  are  first  shredded  upon  scythe  blades — 
i.  e.,  the  seams  are  ripped  open,  buttons  cut  off,  and 
the  dust  shaken  out.  2d.  They  are  steamed  in  a  solu- 
tion of  chloride  of  lime  for  ten  or  twelve  hours  until 
they  are  ikorougldy  bleached.  3d.  They  are  received 


STARCH.  161 

by  a  machine  that  alternately  lacerates  them  by  a 
cylinder  set  with  razor-like  blades,  and  washes  them 
with  pure  cold  water  for  six  hours,  or  until  they  are 
reduced  to  a  mass  resembling  rice  and  milk.  4th. 
This  mass  receives  a  delicate  blue  tint  from  smalt — 
powdered  glass  colored  with  oxyd  of  cobalt.  5th. 
It  is  diluted  with  HO  to  the  consistency  of  city  milk, 
and  sifted,  to  strain  out  the  waxed  ends  and  knots 
of  thread  that  cause  the  provoking  little  lumps  that 
catch  our  pen  when  we  write  rapidly  on  poor  paper. 
6th.  It  flows  over  an  endless  or  circular  belt  of  wire- 
gauze,  about  30  feet  long,  beneath  which  is  a  steam 
air-pump  that  greedily  sucks  down  the  water  from 
the  pulp,  as  it  slowly  passes  along,  gaining  consist- 
ency and  firmness  until  it  comes  to  a  part  of  the  belt 
called  the  "  dandy-roll,"  consisting  of  a  cylinder,  on 
the  surface  of  which  are  wires  arranged  in  parallel 
rows,  or  fancy  letters,  which  print  upon  the  moist 
paper  any  design — constituting  what  are  termed 
"laid,"  "wire-wove,"  or  "water-marks."  7th.  The 
paper,  very  soft  and  moist  as  yet,  but  still  quite 
paperish  in  its  appearance,  passes  between  rollers 
that  squeeze  out  the  water;  then  between  others 
which  are  hot  and  dry  it,  which  bring  it,  8th,  to  a 
vat  of  sizing,  composed  of  the  same  material  as  the 
gelatin  of  calves-foot  jelly,  into  which  it  plunges, 
and  at  the  opposite  side  emerges  only  to  come  be- 
tween other  rollers  that  squeeze  and  dry  it — at  the 
end  of  which  it  passes  under  a  cylinder,  set  with 
knives,  that  clip  the  roll  into  sheets  of  any  desired  size. 


162  ELEMENTARY   CHEMISTRY. 

PARCHMENT  is  prepared  by  plunging  unsized  paper 
for  a  few  seconds  in  SO3  and  HO,  then  washing  off 
the  acid.  This  strengthens  it  in  some  unknown  way, 
and  entirely  changes  its  appearance  and  character, 
so  that  a  narrow  strip  will  support  a  hundred  pound 
weight,  though  before  a  small  fraction  of  that  would 
have  torn  it  instantly. 

LINEN. — This  is  made  from  the  inner  bark  of  flax. 
The  plant  is  first  pulled  from  the  ground  to  preserve 
the  entire  length  of  the  stalk ;  next  "  rotted"  by  ex- 
posure to  air  and  moisture,  when  the  decayed  outer 
bark  is  removed  by  "breaking;"  then,  by  "hatchel- 
ing,"  the  long  fine  fibres  are  divided  into  shreds,  and 
laid  parallel,  while  the  tangled  ones  are  separated 
as  "  tow."  It  is  then  bleached  on  the  grass,  which 
renders  the  gray  coloring-matter  soluble  by  boiling 
in  lye.  The  whitened  flax  is  lastly  woven  into  cloth. 

COTTON  consists  of  the  beautiful  hollow  white  hairs 
arranged  around  the  seed  of  the  cotton-plant.  As 
it  is  always  pure  and  white — except  Nankin  cotton, 
which  is  yellow — it  would  require  no  bleaching  did 
it  not  become  soiled  in  the  process  of  spinning,  etc. 

GUN-COTTON  is  prepared  by  dipping  cellular  tissue 
— cotton,  sawdust,  printing-paper,  etc. — in  strong 
NO5.  It  is  then  carefully  washed  and  dried.  It  is 
not  materially  changed  in  appearance,  although  it 
has  less  strength.  It  sometimes  takes  fire  at  the 
boiling-point  of  HO.  It  explodes  with  much  greater 
violence  and  suddenness  than  gunpowder,  and  for 
that  reason  is  more  liable  to  burst  the  gun. 


STARCH.  1(33 

COLLODION  is  a  solution  of  gun-cotton  in  sulphuric 
ether  and  alcohol.  It  forms  a  syrupy  liquid,  which 
is  an  excellent  substitute  for  courtplaster. 

EREMACAUSIS. — When  wood  decays  slowly  in  the 
open  air,  the  H  passes  off  first,  the  proportion  of  C 
increases,  the  color  darkens,  and  a  black  carbona- 
ceous mass  like  muck  remains,  called  humus.  This 
is  of  great  value  to  the  soil,  as  its  pores  absorb  NH3, 
and  by  its  decay  furnishes  that  and  C02  to  the  grow- 
ing plant.  When  the  supply  of  humus  is  exhausted 
from  the  soil,  we  restore  it  by  adding  straw,  etc.,  and 
by  ploughing  under  green  crops. 

DESTRUCTIVE  DISTILLATION  OF  WOOD. — When  wood 
is  heated  to  a  high  temperature,  with  no  O  present, 
or  an  imperfect  supply,  as  in  our  stoves,  it  is  decom- 
posed, the  charcoal  remains,  while  the  volatile  con- 
stituents pass  over  in  the  form  of  illuminating  gas, 
HO,  pyroligneous  acid,  and  wood-tar.  This  latter  is 
a  thick  liquid  used  for  calking  and  tarring  ships :  on 
distillation  it  yields  benzole,  creosote,  and  paraffins. 

PYROLIGNEOUS  ACID  (wood-vinegar)  is  obtained  by 
the  distillation  of  beech-wood.  It  contains  much 
creosote  and  acetic  acid.  On  account  of  the  former 
property  it  is  used  for  curing  hams  in  commerce,  and 
on  account  of  the  latter,  for  making  salts  called 
acetates. 

CREOSOTE  (flesh  preserver)  is  a  colorless  liquid  with 
a  flavor  of  burnt  wood.  It  is  poisonous  when  taken 
in  any  quantity.  It  is  a  powerful  antiseptic,  and  a 
mixture  of  1  part  creosote  in  100  parts  HO  will,  in  a 


164  ELEMENTARY  -CHEMISTRY. 

few  hours,  give  a  ham  a  delicate  smoky  flavor  and 
render  it  incapable  of  putrefaction.  Creosote  im- 
parts to  smoke  its  characteristic  odor,  and  renders  it 
so  irritating  to  the  eyes,  and  also  gives  to  it  the 
power  of  curing  hams,  dried  beef,  etc. 

TAR  is  made,  like  charcoal,  by  burning  heaps  of 
wood  under  a  covering  of  earth  which  excludes  the 
air:  an  imperfect  combustion  ensues,  the  resinous 
matter  exudes,  and,  trickling  down  to  the  hollow 
bottom,  collects  and  runs  into  a  reservoir.  On  the 
extensive  pine-barrens  of  North  Carolina  the  tar  of 
commerce  is  principally  produced. 

TURPENTINE. — When  tar  is  distilled  it  separates 
into  pitch,  which  remains,  and  oil  of  turpentine,  which 
passes  off.  The  latter,  redistilled,  forms  the  rectified 
"  spirits  of  turpentine."  The  residuum  of  the  distil- 
lation is  called  "rosin." 

COAL-TAR  is  formed,  as  we  have  seen,  in  the  process 
of  making  illuminating  gas.  This  was  formerly 
thought  valueless,  but  is  now  used  for  a  variety  of 
purposes.  As  a  cement  for  roofs,  walks,  and  pave- 
ments, for  oiling  machinery,  and  preserving  wood 
from  decay,  it  is  invaluable.  On  distillation  it 
yields  the  following,  among  other  products:  1st, 
lenzole  (benzine),  used  as  a  solvent  for  gutta-percha, 
caoutchouc,  wax,  and  for  removing  grease-spots. 
This,  by  distilling  with  NO5,  gives  nitro-benzole, 
which  so  nearly  resembles  the  oil  of  bitter  almonds 
that  it  is  used  for  it  in  perfumery,  confectionery, 
etc.  By  heating  it  with  acetic  acid  and  iron-£lings 


STARCH.  165 

anaUne  is  commonly  prepared.  2d,  Par&ffine,  a  hard, 
white,  tasteless  solid,  like  spermaceti.  It  forms 
beautiful  candles,  which  look  and  burn  like  the 
finest  of  wax.  3d,  Analine,  from  which  some  of  the 
most  exquisite  colors  of  every  shade  are  produced. 
Example  :  Mauve,  magenta.  When  first  prepared, 
analine  was  worth  more  than  gold,  and  is  even  now 
expensive  ;  but  its  dyeing  properties  are  very  intense. 
(Who  but  a  chemist  would  have  searched  for  such 
brilliant  colors  in  coal-tar !)  4th,  Carbolic  add,  which, 
by  heating  with  NO5,  dyes  a  rich  yellow ;  it  is  also 
used  as-  a  disinfectant.  The  production  of  dye-stuffs 
from  coal-tar  formed  an  era  in  organic  chemistry, 
and  revolutionized  the  whole  art  of  dyeing  and 
calico-printing. 

PETROLEUM  is  doubtless  the  product  of  the  distil- 
lation of  organic  matter  beneath  the  surface  of  the 
earth.  It  is  not  always  connected  with  coal,  as  it  is 
often  found  outside  the  coal-measures,  as  in  North- 
western Pennsylvania  and  New  York.  The  distilla- 
tion must  have  taken  place  at  a  much  greater  depth 
than  that  at  which  the  oil  is  now  found,  as  it  would 
naturally  rise  through  the  fissures  of  the  rock  and 
gather  in  the  cavities  above.  Sometimes  the  oil  has 
collected  on  the  surface  of  subterranean  pools  of 
salt-water,  so  that  after  a  time  the  oil  is  exhausted, 
and  salt-water  only  is  pumped  up ;  or  if  the  well 
strikes  the  lower  part  of  the  cavity,  the  water  will 
first  be  pumped  and  afterward  the  oil.  The  crude 
oil  from  the  well  is  purified  by  distillation.  That 


166  ELEMENTARY  CHEMISTRY. 

which  passes  over  at  the  lowest  temperature  is  called 
naphtha :  as  the  heat  is  increased,  there  passes  over 
next  the  kerosene  oil  for  illumination,  and  lastly  the 
lubricating  oil.  The  kerosene  is  deodorized  and 
decolorized  by  the  use  of  sugar  of  lead,  SO3,  KO, 
and  other  chemicals,  which  are  stirred  in  the  oil, 
after  which  it  is  redistilled. 

Bitumen  or  Asphaltum. — Petroleum  (petra,  a  rock, 
and  oleum,  oil)  and  naphtha,  flowing  from  the 
ground,  have  formed  beds  of  bitumen  in  various 
parts  of  the  world.  This  change  is  caused  by  a 
gradual  oxydation  and  hardening,  as  turpentine 
changes  to  rosin.  On  the  island  of  Trinidad  is  a 
lake  called  Tar  Lake.  It  is  nearly  three  miles  in 
circumference.  Below  it  is  a  bed  of  coal,  from  which 
the  oil  is  doubtless  distilled.  The  bitumen  from  the 
lake  is  used  for  the  same  purposes  as  pitch,  which 
it  closely  resembles.  Near  the  shore  it  is  hard  and 
compact,  except  in  hot  weather,  when  it  becomes 
sticky.  At  the  centre  it  is  soft,  and  fresh  bitumen 
boils  up  to  the  surface.  Asphaltum  is  found  in  im- 
mense quantities  in  California  and  in  Canada.  It  is 
a  natural  cement  for  laying  stone  or  brick.  It  was 
used  in  building  the  walls  of  Babylon,  for  which 
purpose  it  was  gathered  from  the  fountain  of  Is  on 
the  banks  of  the  Euphrates.  It  was  a  prominent 
ingredient  in  the  "  Greek  Fire,"  so  much  used  by 
the  nations  of  Eastern  Europe  in  their  naval  wars, 
even  as  late  as  the  fourteenth  century.  This  con- 
sisted of  bitumen,  sulphur,  and  pitch,  which  was 


STARCH.  167 

thrown  through  long  copper  tubes,  from  hideous 
figures  erected  on  the  prow  of  the  vessel.  It  was 
said  to  be  inextinguishable  except  by  wine  or  vine- 
gar. Bitumen  is  used  in  making  the  famous  prome- 
nades of  the  Boulevards  in  Paris. 

CANE-SUGAR  (C12HnOu)*  is  obtained  from  the  sap 
of  the  sugar-maple,  sugar-cane,  sorghum,  and  the 
juice  of  the  beet.  In  making  it  from  the  sugar-cane, 
the  canes  are  crushed  between  iron  cylinders,  thus 
expressing  the  juice.  As  it  sours  very  soon,  from 
the  heat  of  the  climate  in  which  it  grows,  a  little 
lime  is  added  to  neutralize  the  acid,  and  it  is  then 
evaporated  to  a  thick  jelly,  and  set  aside  to  cool. 
The  sugar  crystallizes  readily,  forming  brown  sugar, 
which  is  put  in  perforated  casks  to  drain.  The 
drainings  constitute  molasses. 

Refining  of  Sugar. — Brown  sugar  is  refined  by  dis- 
solving it  in  HO,  then  adding  albumen  (whites  of 
eggs,  blood,  etc.),  which,  on  heating,  coagulates  and 
settles  to  the  bottom  with  the  coarser  impurities. 
The  solution  is  then  filtered  through  animal  charcoal, 

*  Ex. :  A  very  brilliant  illustration  of  the  presence  of  C  in 
C,aHI1OIl  is  obtained  by  putting  on  a  clean  white  plate  a  mixture 
of  finely  pulverized  white  sugar  and  KO.C1O6.  Upon  adding  a 
few  drops  of  SO3,  a  vivid  combustion  will  ensue.  By  mixing 
also  a  few  iron  and  steel  filings,  and  performing  the  experiment 
in  a  dark  room,  or  out  of  doors  at  night,  fiery  rosettes  will  flash 
through  a  rose-colored  flame,  and  produce  a  fine  effect.  The 
contrast  between  the  white  plate  and  mixture  and  the  dense  black 
carbonaceous  compound  covering  the  adjacent  floor,  is  very  strik- 
ing to  the  eye. 


168  ELEMENTARY  CHEMISTRY. 

and  finally  evaporated  in  vacuum-pans,  from  which 
the  air  is  exhausted,  so  that  the  sugar  boils  at  140°F., 
and  all  danger  of  burning  is  avoided.  From  this 
the  sugar  crystallizes,  and  the  white  sugar  is  set  aside 
to  drain.  The  drainings  constitute  "  syrup,"  "  sugar- 
house  molasses,"  etc. 

BOCK  CANDY  is  formed  by  suspending  threads  in  a 
strong  solution  of  sugar.  It  crystallizes  upon  the 
rough  surface  in  large  six-sided  prisms. 

CONFECTIONERY  is  commonly  supposed  to  be  made 
from  sugar.  Alba  terra  (white  earth)  is  now  largely 
imported  from  Ireland  for  use  in  lozenges,  candy 
drops,  etc.,  enough  sugar  only  to  flavor  being  added. 
We  can  and  should  test  all  the  candy  we  purchase 
by  putting  a  small  piece  in  a  glass  of  water.  What- 
ever settles  to  the  bottom  cannot  be  sugar,  but  is  a 
vile  adulteration.  Candies  also  are  often  colored  by 
the  direst  poisons,  so  that  prudence  would  forbid 
the  use  of  any  colored  candy  whatsoever.  The 
grocer  or  dealer  is  as  liable  to  be  mistaken  or  igno- 
rant in  regard  to  the  purity  of  his  candies  as  we 
ourselves.  Licorice  drops  are  frequently  only  the 
poorest  brown  sugar,  terra  alba,  and  a  flavoring  of 
licorice  to  make  the  unwholesome  mixture  palatable. 
Gum-drops  are  generally  made,  not  from  gum-arabic, 
but  the  best  kinds  are  composed  of  a  species  of  glue 
manufactured  out  of  hoofs,  parings  of  hides,  offal, 
etc.,  from  the  slaughter-houses.  And  yet,  however 
repugnant  it  may  appear,  this  glue  is  perfectly  clean 
and  wholesomj.  Many  kinds  of  gum-drops  and 


STARCH.  169 

lozenges  are  made  from  dextrine,  terra  alba,  plaster 
of  Paris,  a  little  sugar,  and  some  flavoring  extract. 

CAROMEL,  familiarly  called  burnt  sugar,  is  formed 
whenever  sugar  is  heated  above  400°  F.,  when  it 
parts  with  four  equivalents  of  water,  leaving  the  C 
in  excess,  as  when  sweetmeats  boil  over  on  the  stove. 
It  is  used  extensively  in  coloring  liquors. 

GRAPE-SUGAR  (C12H.UOU). — This  variety  of  sugar 
includes  the  sugar  of  grapes,  figs,  all  common  fruits, 
honey,  etc.,  in  which  forms  we  are  familiar  with  it. 
It  has  much  less  sweetness  than  cane-sugar. 

SUGAR  FROM  STARCH  OR  WOOD. — Starch  and  woody 
fibre  differ  only  from  grape-sugar  by  four  atoms  of 
HO.  By  slowly  heating  with  SO3,  diluted  largely 
with  HO,  common  sawdust,  paper,  and  old  rags 
even,  can  be  converted  into  sugar.  Indeed,  Profes- 
sor Pepper  speaks  of  eating  a  fine  quality  of  grape- 
sugar  made  out  of  an  old  flannel  shirt  he  had  out- 
grown. The  weight  of  sugar  exceeds  that  of  the 
woody  fibre  used  by  the  additional  four  elements 
of  HO.  This  change  takes  place  in  the  plant.  The 
green  fruit  contains  starch,  which,  as  the  fruit  ripens, 
is  turned  into  grape-sugar.  If  it  over-ripens,  the 
sweetness  is  lost,  as  the  sugar  is  reabsorbed  by  the 
plant  and  converted  into  woody  fibre  again.  In  the 
sap  of  the  sugar-maple  tree  there  is  much  grape- 
sugar,  but  as  the  leaves  start  they  hasten  to  stop  this 
pilfering  of  their  sweet  juices  by  turning  it  into 
cellular  tissue — into  the  wood  of  the  tree.  The 
farmer  knows  that  if  he  does  not  cut  his  grass  at  the 

8 


170  ELEMENTARY  CHEMISTRY. 

proper  time  it  will  undergo  this  change,  and  become 
tough  and  tasteless  and  of  little  value  to  him.  The 
starch  in  potatoes  is  turned  to  sugar  by  freezing,  and 
so  frozen  potatoes  taste  sweet. 


FEKMENTATION. 

If  a  solution  of  starch  or  sugar  be  exposed  to  the 
air  it  will  undergo  no  change,  but  if  there  be  added 
a  little  ferment  or  yeast,  flour-paste,  or  any  albu- 
minous substance  (i.  e.,  one  containing  N),  in  a  de- 
composing state,  it  will  immediately  commence 
breaking  up  into  new  compounds.  There  are  two 
stages  in  this  chemical  change. 

1st.  ALCOHOLIC  FERMENTATION. — In  this,  the  sugar 
is  resolved  into  alcohol,  water,  and  carbonic  acid.  The 
two  former  remain  in  the  liquid,  while  the  latter 
escapes  in  little  bubbles  of  gas.  The  reaction  is  as 

follows : 

Hu 


2d.  ACETOUS  FERMENTATION. — The  second  stage 
succeeds  the  first  immediately,  if  not  checked,  and 
by  absorbing  oxygen  from  the  air,  the  alcohol  is  broken 
up  into  acetic  add  and  water. 


FERMENTATION.  171 

C4  H6  O2  4-  04  (from  tlie  air) 


C4  H4  O4  +  2HO 


YEAST  is  composed  of  microscopic  plants  formed 
during  the  process  of  fermentation.  So  minute  are 
they,  that  it  is  said  a  cubic  inch  contains  1,200,000,000 
of  them.  In  the  malting  of  barley  they  spring  up 
in  great  abundance,  making  common  brewer's  yeast. 
The  yeast-cakes  of  the  kitchen  are  formed  by  expos- 
ing moistened  Indian  meal,  containing  a  ferment,  to 
a  moderate  temperature  until  the  gluten  or  albu- 
minous matter  of  the  cake  has  undergone  this  alco- 
holic fermentation.  It  is  then,  laid  aside  for  use.  A 
heat  of  212°,  or  a  cold  of  10°,  will  kill  the  yeast 
plant  and  destroy  its  efficiency  as  a  ferment. 

MALT. — In  making  malt,  the  barley  is  thoroughly 
moistened,  and  then  spread  on  the  floor  of  a  dark 
room  (malting-room),  to  heat  and  sprout.  Here  a 
curious  change  ensues,  identical  with  that  which 
takes  place  in  every  planted  seed.  Each  one  con- 
tains starch  and  a  nitrogenous  substance  called  glu- 
ten. The  tiny  plant  not  being  able  to  support  itself 
in  the  beginning,  has  here  a  little  patrimony  to  start 
with  in  life,  but,  as  the  starch  is  insoluble  in  its  sap, 
it  must  first  be  changed  to  sugar.  We  see,  there- 
fore, the  need  of  a  ferment ;  but  it  would  not  answer 
to  store  up  in  the  seed  an  active  ferment,  as  that 
might  cause  a  change  befcre  the  plant  was  ready  to 


172  ELEMENTARY   CHEMISTRY. 

grow,  and  thus  the  plant's  capital  be  wasted.  The 
gluten  is  therefore  a  latent  ferment,  as  it  were.  As 
soon  as  the  seed  is  planted  it  absorbs  moisture  from 
the  ground,  is  turned  into  diastase — an  active  fer- 
ment— the  starch  is  converted  into  sugar,  dissolved, 
and  immediately  applied  to  the  uses  of  the  growing 
plant.  This  change  takes  place  in  the  malting-room. 
The  barley  sprouts,  and  a  part  of  its  starch  is 
turned  to  sugar,  so  that  it  tastes  quite  sweet.  If 
this  germination  were  allowed  to  proceed,  the  little 
barley  sprout  would  turn  this  sugar  into  woody  fibre. 
To  prevent  this  the  grain  is  heated  in  a  kiln  until 
the  germ  is  destroyed.  Barley  in  this  condition  is 
called  malt,  and  is  then  transported  to  the  breweries. 

BREWING  BEER. — The  malt  is  crushed  and  digested 
in  water,  to  convert  all  the  remaining  starch  into 
sugar.  Having  been  boiled,  to  clarify  it,  hops  and 
yeast  are  added,  and  fermentation  immediately  com- 
mences. Bubbles  of  gas  rise  to  the  top  with  a  low 
hissing  sound,  yeast  gathers  into  a  foamy  cream  that 
comes  to  the  surface  of  the  tub,  and  the  alcohol 
gradually  accumulates  in  the  liquid.  It  is  now 
drawn  off  into  tight  casks,  where  it  undergoes  a  sec- 
ond fermentation ;  the  flavor  of  the  beer  ripens,  and 
the  CO2  collecting,  gives  to  the  liquor,  when  drawn, 
its  sparkling,  foamy  appearance. 

LAGER  BEER  (Lagen,  to  lie)  is  so  called  because 
it  is  allowed  to  lie  for  months  in  a  cool  cellar,  where 
it  ripens  very  gradually.  It  is  also  fermented  much 
more  dowly  and  perfectly  than  ale  or  porter. 


FERMENTATION.  173 

WINES  are  commonly  made  from  the  juice  of  the 
grape.  The  juice,  or  must,  as  it  is  called,  is  placed 
in  vats  in  the  cellar,  where  the  low  temperature  pro- 
duces a  very  slow  fermentation.  Before  the  sugar 
is  all  converted  into  CO2  and  alcohol,  the  wine  is 
bottled.  The  undecomposed  sugar  gives  the  flavor 
to  sweet  wines,  while  the  CO2,  formed  afterward  and 
dissolved  in  the  liquid,  produces  the  effervescence  of 
sparkling  wines.  The  sugar  keeps  the  wine  and 
rather  improves  its  body  for  even  a  couple  of  centu- 
ries. The  bouquet,  or  flavor  of  wines,  is  given  by  a 
very  volatile  liquid  called  cenanthic  ether.  It  is  de- 
veloped in  its  perfection  by  age  alone,  and  gives  the 
value  to  old  wines.  The  acidity  of  wine  is  due  to  a 
small  quantity  of  tartaric  acid  combined  with  KO, 
forming  the  bitartrate  of  potash  (cream  of  tartar), 
which  gradually  separates  and  collects  upon  the 
sides  and  bottoms  of  the  casks  and  bottles  in  a 
white  incrustation. 

ALCOHOL  IN  BEER  AND  WINE. — Alcohol  is  the  in- 
toxicating principle  alike  of  all  varieties  of  liquors, 
ale,  beer,  wine,  cider,  and  the  domestic  wines.  Ale 
contains  from  five  to  ten  per  cent,  of  alcohol ;  wine 
varies  from  five  per  cent,  in  the  light  Champagne  to 
twenty-five  per  cent,  in  the  strong  Port,  Madeira,  or 
Sherry. 

ARDENT  SPIRITS. — When  any  fermented  liquor  is 
distilled,  the  alcohol  passes  over  at  a  temperature 
of  173°,  together  with  some  water  and  fragrant 
substances  which  are  condensed.  In  this  way 


174  ELEMENTARY   CHEMISTRY. 

brandy  is  made  from  wine  ;  rum  from  fermented 
molasses  ;  whiskey  from  fermented  corn,  rye,  or  po- 
tatoes ;  gin  from  fermented  barley  and  rye,  after- 
ward redistilled  with  juniper-berries  ;  alcohol  alone 
from  whiskey.  The  percentage  of  alcohol  in  these 
spirituous  liquors  varies  from  fifty  to  seventy  per 
cent.  The  accompanying  cut  represents  an  appara- 
tus used  for  this  distillation.  A  is  the  boiler,  B  the 


A  Still. 


dome,  C  a  tube  passing  into  S,  the  condenser,  where 
it  is  twisted  into  a   spiral  form  called  the  worm,  in 
which  the  vapor  from  the  boiler  is  condensed,  and 
drops  out  at  D. 
ALCOHOL  (C4H6O2)  is  prepared  by  distilling  whiskey, 


FERMENTATION.  175 

and  is  sometimes  called  spirits  of  wine.  It  boils  at 
173°,  and  has  never  been  frozen  even  at  —166°  F.  It 
contains,  when  purest,  ten  per  cent,  of  HO,  which 
can  be  separated  by  adding  some  substance  like 
CaCl,  which  has  a  strong  affinity  for  HO.  It  is 
then  called  anhydrous  or  absolute  alcohol.  When 
C4H6O2  is  exposed  to  the  air  the  spirit  evaporates, 
while  it  also  attracts  moisture  from  the  atmosphere. 
The  chemist  discovers  this  when  he  neglects  to  put 
the  extinguisher  on  his  alcohol-lamp  and  finds  that 
he  cannot  relight  it  without  moistening  the  wick 
with  fresh  alcohol.  It  burns  without  smoke  and 
with  intense  heat,  owing  to  the  abundance  of  H  and 
deficiency  of  C,  and  is  therefore  of  great  value  in 
the  arts.  It  is  also  of  incalculable  importance  as  a 
solvent  in  forming  tinctures  of  many  substances — 
roots,  resins,  fragrant  oils,  etc. 

Effects  of  Alcohol.— When  pure  it  is  a  deadly  poison. 
When  diluted,  as  in  the  ordinary  liquors,  it  is  stimu- 
lative and  intoxicating.  Its  influence  is  on  the 
brain  and  nervous  system ; — deadening  the  natural 
affections,  dulling  the  intellectual  operations  and 
moral  instincts  ;  seeming  to  pervert  and  destroy  all 
that  is  pure  and  holy  in  man,  while  it  robs  him  of 
his  highest  attribute — reason.  It  is  a  blight  upon  a 
family,  a  curse  to  society,  and  the  bane  of  our  civili- 
zation. In  a  word,  alcohol  makes  drunkards,  and 
a  drunkard  is  the  saddest,  most  shocking  sight  this 
world  affords. 

ETHEK  (CJI5O). — Sulphuric  ether  is  formed  by  the 


176  ELEMENTARY  CHEMISTRY. 

distillation  of  C4HGO2  with  SO3.  The  SO3  simply 
takes  an  atom  of  HO  out  of  the  alcohol.  It  has  a 
fragrant  odor,  boils  at  96°,  and  burns  with  more 
light  and  smoke  but  less  heat  than  alcohol.  By  the 
action  of  the  other  acids  on  CiUjC^  varieties  of 
ether  are  produced — viz.,  nitric  ether,  carbonic 
ether,  etc. 

AMYLIC  ALCOHOL  (fusel  ail)  is  one  of  a  large  class 
of  substances  similar  to  alcohol,  and  thus  called  "  the 
alcohols."  It  is  formed  in  distilling  whiskey  from 
potatoes.  It  is  present  in  common  C4H6O2,  giving 
that  slightly  unpleasant  odor  when  it  evaporates 
from  the  hand.  It  is  extremely  poisonous,  and 
though  contained  in  liquors  in  very  small  quantities, 
is  said  to  greatly  increase  their  destructive  and  in- 
toxicating properties.  It  is  of  interest,  mainly  be- 
cause by  distilling  it  with  different  acids,  various 
products  are  obtained,  having  the  most  delicate 
flavor  and  odor.  Pear,  apple,  orange,  and  many 
other  "  flavoring  essences"  are  thus  prepared.  Though 
made  from  the  poisonous  fusel  oil,  they  are  perfectly 
innocuous. 

CHLOROFORM  (C2HC1)  is  made  by  distilling  C4H6O2 
with  chloride  of  lime.  It  is  colorless,  volatile,  of 
a  sweet  taste,  and  should  be  free  from  any  unpleas- 
ant odor  when  evaporated  on  the  hand.  It  is  mainly 
used  as  an  anaesthetic.  The  value  of  ether  and 
chloroform  in  alleviating  pain,  is  beyond  estimate. 
On  the  battle-field,  in  hospitals,  everywhere,  our 
soldiers  have  sunk  into  pleasant  slumber,  while  the 


FERMENTATION.  177 

most  painful  surgical    operations  have  been  per- 
formed. 

ACETIC  ACID  (C4H4O4,  A).— When  any  fermenting 
substance  has  reached  the  first  stage — the  alcoholic 
fermentation — if  the  process  be  not  stopped,  it  passes 
on  to  the  second — the  acetous  fermentation,  forming 
acetic  acid  and  water.  This  acid  is  well  known  as 
common  vinegar,  of  which  it  forms  about  five  per 
cent.  The  acid  of  commerce  is  prepared  by  the 
action  of  SO3  on  acetate  of  lead  (sugar  of  lead) 
PbO .  A.  The  reaction  is — 

PbO.l  +  SO3 


PbO.SO3  +  A. 

CIDEK  YINEGAE. — Cider  contains  some  nitrogenous 
matter,  which  acts  as  a  ferment,  and  the  vinegar  of 
the  apple  is  broken  up  into  alcohol  and  carbonic 
acid.  This  makes  what  is  called  "  old  cider."  By  ex- 
posure to  the  air  and  heat,  which  always  hastens 
chemical  change,  the  alcohol  passes  on  to  the  second 
stage,  and  the  acetic  acid  formed  produces  the  sour 
taste  of  the  vinegar.  "  Mother"  in  vinegar,  is  a  plant 
produced  by  the  decomposition  of  the  nitrogenous 
matter.  It  acts  as  a  ferment,  and  frequently  generates 
a  nation  of  infusoria — vinegar  eels.  Acetic  acid  is 
a  solvent  of  albumen,  gelatin,  fibrin,  etc.  Hence  it 
takes  from  meat,  eggs,  oysters,  etc.,  pickled  in  it, 
their  most  strengthening  constituents.  For  the 


178  ELEMENTABY  CHEMISTEY. 

same  reason,  vinegar  is  a  valuable  assistant  in  digest- 
ing such  food.  It  allays  thirst,  and  was  anciently 
carried  by  the  Boman  soldiers  in  a  little  flask  for 
that  purpose.  In  the  case  of  young  ladies  who  use 
it  (as  well  as  slate-pencils),  to  relieve  corpulency,  it 
produces  delicacy  and  finally  consumption.  Any 
sugar  added  to  vinegar  quickly  passes  to  the  second 
stage  of  fermentation,  and  increases  its  strength. 
Indeed,  vinegar  is  sometimes  made  entirely  from 
tea-leaves,  which  act  as  the  ferment,  and  sweetened 
water.  Vinegars  of  commerce  are  frequently  sharp- 
ened by  the  addition  of  SO3  and  pungent  spices. 
We  can  easily  detect  these  by  evaporating  a  half- 
gill  in  a  saucer,  placed  over  boiling  water.  As  it 
boils  down,  add  a  little  honey.  If  the  grape-sugar 
it  contains  turns  black,  it  is  proof  of  the  presence  of 
SO3.  As  the  last  of  the  liquid  evaporates,  the  odor 
of  cayenne  pepper,  etc.  (if  there  be  any),  can  be 
readily  distinguished. 

A  new  Method. — The  following  method  has  lately 
been  adopted  in  England.  A  thin  liquid  made  from 
malt  and  HO  is  allowed  to  pass  into  the  first  stage 
of  fermentation.  A  large  vat  is  filled  with  short 
pieces  of  wicker-work,  which  are  kept  wet  with  an 
old  vinegar  wash  until  the  surface  of  the  wicker-work 
is  covered  with  young  vinegar-plants;  these  grow 
until  they  fill  all  the  empty  space.  The  weak  alco- 
holic liquid  is  now  permitted  to  trickle  down  through 
this  vat  full  of  mother,  while  at  the  same  time  the 
heat  of  the  chemical  change  causes  an  upward  cur- 


FERMENTATION.  179 

rent  of  air  through  holes  at  the  bottom  of  the  vat. 
Before  the  liquid  reaches  the  faucet  below,  it  presses 
into  the  second  stage  of  fermentation. 

QUICK  VINEGAR  PROCESS. — Vinegar  is  now  made 
on  a  large  scale  by  filtering  a  mix- 
ture of  alcohol  and  yeast  through  a 
cask  filled  with  beech  shavings 
soaked  in  vinegar.  As  the  ferment- 
ing alcohol  slowly  trickles  down,  it 
comes  in  close  contact  with  the  air, 
absorbing  O  so  rapidly  that  some- 
times before  it  reaches  the  bottom 
it  becomes  entirely  converted  into  vinegar. 

PRESERVES  frequently  work,  as  it  is  called,  and 
then  sour.  The  bubbles  of  gas  which  rise  to  the 
surface  indicate  the  first  or  alcoholic  stage  of  fer- 
mentation. If  neglected,  this  soon  passes  to  the 
second.  It  may  be  checked  by  scalding,  which  de- 
stroys the  ferment. 

VEGETABLE  ACIDS. 

There  are  many  of  these  found  native  in  plants — 
most  generally,  however,  combined  with  some  base. 

OXALIC  ACID  (C4H6;  O)  is  familiar  in  the  sour  taste 
of  pie-plant,  sorrel,  etc.,  in  which  it  is  combined  with 
KO,  which  largely  neutralizes  its  acid  properties. 
It  is  prepared  by  the  action  of  NO5  on  sugar.*  O 

*  Oxalic  acid  is  also  made  on  a  large  scale  from  sawdust, 
soda,  and  potash.  The  woody  fibre  is  resolved  into  oxalic  acid, 


180  ELEMENTARY  CHEMISTRY. 

is  a  potent  poison.  Its  antidote  is  a  drink  of  pow- 
dered magnesia,  or  chalk,  stirred  in  HO.  It  is  a 
test  of  lime,  forming  a  delicate  white  precipitate  of 
oxalate  of  lime.  Its  solution  is  much  used  to  re- 
move ink  stains,  and  it  is  sold  for  this  purpose  under 
the  deceptive  and  dangerous  name  of  "  salts  of 
lemon."  The  acid  unites  with  the  iron  of  the  ink, 
and  the  oxalate  of  iron  thus  made  is  easily  dis- 
solved in  HO.  It  should  be  thus  washed  out  im- 
mediately, as  it  will  corrode  the  cloth.  The  crystals 
of  O,  it  should  be  noticed,  very  much  resemble  those 
of  Epsom  salts,  and  many  serious  mistakes  have  oc- 
curred in  consequence. 

TARTARIC  ACID  (C8H4O10,  T)  exists  in  many  fruits, 
principally  in  the  grape,  combined  with  KO  as 
KO.2T,  the  bitartrate  of  potassa.  This  settles  during 
the  making  of  wine,  as  we  have  seen,  and  when  puri- 
fied is  called  cream  of  tartar.  From  this  T  is  made. 
It  forms  large,  colorless  crystals,  of  a  pleasant  acid 
taste,  which  are  permanent  in  the  air.  Its  solution 
gradually  becomes  mouldy  and  turns  into  A.  Eo- 
clielle  salt  is  a  double  tartrate  of  potassa  and  soda  ; 
it  is  a  purgative,  and  is  much  used  in  Kochelle,  or 
S&idlitz,  powders.  These  are  combined  in  a  blue  and 
a  white  paper.  The  former  holds  120  grains  of 
Rochelle  salt,  and  40  grains  of  bicarbonate  of  soda ; 

which  combines  with  the  bases,  forming  oxalates  of  soda  and 
potash.  From  these  the  acid  is  readily  obtained.  Sawdust  will 
yield  more  than  half  its  weight  of  crystals  of  this  salt 


VEGETABLE  ACIDS.  181 

the  latter  35  grains  of  tartaric  acid.  These  are  dis- 
solved in  separate  goblets.  The  one  containing  the 
acid  is  emptied  into  the  other,  when  the  CO2  is  set 
free,  producing  a  violent  effervescence  and  disguis- 
ing the  taste  of  the  medicine.  Tartar  emetic  is  a 
double  tartrate  of  potassa  and  antimony. 

CITEIC  ACID  (citrus,  lemon)  is  the  sour  principle  of 
the  citron,  orange,  lemon,  cranberry,  etc.  It  is  com- 
bined with  lime  in  the  onion. 

MALIC  ACID  (medics,  an  apple)  is  found  in  the  apple, 
peach,  pear,  plum,  cherry,  etc. 

TANNIC  ACID  (tannin)  is  found  in  the  leaves  and 
bark  of  many  trees.  Example  :  Oak,  hemlock,  su- 
mach. Nutgalls  is  an  excrescence  which  forms  on 
oak-trees  \dien  punctured  by  insects  for  the  purpose 
of  laying  their  eggs.  Tea  and  coffee  contain  from  8 
to  10  per  cent,  of  tannin.  It  has  a  bitter,  astrin- 
gent, puckering  taste,  is  soluble  in  water,  and  har- 
dens all  albuminous  substances,  such  as  gelatine, 
etc. 

TANNING. — After  the  hair  has  been  removed  from 
the  skins  by  milk  o  lime,  they  are  soaked  for  days, 
the  best  kinds  for  months,  in  vats  full  of  water  and 
ground  oak  or  hemlock  bark  (tan-bark).  The  tannic 
acid  of  the  bark  is  dissolved,  and  entering  the  pores 
of  the  skin,  unites  with  the  gelatin,  forming  a  hard 
insoluble  compound  which  is  the  basis  of  leather. 
Leather  is  blackened  by  washing  the  hide  on  on  3 
side  with  a  solution  of  copperas  (FeO.SO3).  Ths 
tannic  acid  unite .  v>.th  the  iron,  forming  a  tannuta 


182  ELEMENTARY  CHEMISTEY. 

of  iron — a  real  ink.  In  the  same  way  drops  of  tea 
on  a  knife-blade  stain  it  black. 

INK  is  made  by  adding  a  solution  of  nutgalls  to 
one  of  copperas.  The  tannate  of  iron  thus  formed 
has  a  pale  blue-black  color,  as  in  the  best  writing- 
inks.  By  exposure  to  the  air  the  iron  absorbs  more 
O,  and  becomes  changed  from  the  protoxide  to  the 
sesquioxide,  thus  darkening  in  color  until  it  is  a 
deep  black.  Gum-arabic  is  added  to  the  ink  to 
thicken  it  and  regulate  its  flow  from  the  pen.  Cloves 
or  corrosive  sublimate  are  used  to  prevent  mouldi- 
ness.  Steel  pens  are  corroded  by  the  free  SO3  con- 
tained in  the  ink,  but  gold  pens  are  not  affected  by  it. 

Experiment. — The  following  is  an  instructive  ex- 
periment, illustrating  the  manner  of  making  ink, 
of  removing  stains  with  oxalic  acid,  and  also  the 
relative  strength  of  the  acids  and  alkalies.  Take  a 
large  test-tube,  and  add  the  following  reagents  in 
solution  cautiously,  drop  by  drop,  watching  the  re- 
sult and  explaining  the  reactions  : 

Sulphate  of  iron  (copperas) FeO .  SO3 

Tannic  acid  (tannin) Cs4  Has  Oa4 

Oxalic  acid C4  H, 

Carbonate  of  soda  (sal-soda) NaO .  COa 

Hydrochloric  acid  (muriatic) HC1 

Ammonia  (hartsliorn) NH3 

Nitric  acid  (aquafortis) NO6 

Potassa  (potash) KO 

Sulphuric  acid  (oil  of  vitriol) SOS 

GALLIC  ACID  is  always  a  companion  of  tannin  in 


OILS  AND  FATS.  183 

the  substances  we  have  named,  and  is  formed 
from  it  by  exposure  to  the  air.  In  some  hair-dyes 
the  hair  is  first  wet  with  gallic  acid,  and  then  with  a 
solution  of  nitrate  of  silver.  The  acid  decomposes 
the  salt,  and  the  liberated  oxyd  of  silver  colors  the 
hair. 


OILS  AND  FATS. 

The  difference  between  oils  and  fats  is  only  that 
of  temperature;  the  former  remain  liquid  at  ordi- 
nary degrees  of  heat,  while  the  latter  is  a  solid.  "  A 
fat  may  be  called  a  solid  oil,  and  an  oil  a  liquid  fat," 
with  equal  propriety.  The  peculiar  odor  of  each  is 
due  to  some  volatile  acid.  They  are  divided  into 
two  classes — fixed  oils  and  volatile  oils.  The  former 
produce  a  permanent  stain  on  paper,  the  latter  do 
not.  "  A  cork  twisted  into  the  neck  of  a  bottle  con- 
taining a  fixed  oil  makes  no  noise ;  in  a  volatile  oil 
it  squeaks.' 

THE  FIXED  OILS. 

Constitution. — All  fatty  bodies  are  salts,  being 
composed  of  stearin,  margarin,  and  olein.  These 
consist  of  three  acids — stearic,  margaric,  and  oleic, 
combined  with  a  common  base,  glycerin ;  thus : 

Stearic  acid,     )  (  Stearin. 

Margaric  acid,  >•  with  Glycerin  (as  a  base),  form  -<  Margarin. 
Oleic  acid,        )  •      (  Olein. 


184  ELEMENTARY  CHEMISTRY. 

The  first  two  of  these  salts  are  solids  at  common 
temperatures,  and  form  fats ;  the  latter  is  a  liquid, 
and  forms  oils.  The  relative  proportion  of  olein 
contained  in  any  fatty  substance  determines  its  flu- 
idity. Ex. :  Stearin  is  abundant  in  tallow,  and  mar- 
garin  in  butter,  hence  their  comparative  consistency. 
Lard,  on  the  other  hand,  contains  so  much  olein  that 
it  is  expressed  in  large  quantities  as  "  lard-oil."  Olive- 
oil  contains  much  olein  and  margarin;  the  former 
remains  fluid  at  ordinary  temperatures,  but  the 
latter,  in  cold  weather,  hardens  into  a  thick  deposit, 
and  renders  the  oil  extremely  viscid. 

GLYCERIN  is  named  from  its  sweet  taste.  It  is 
made  from  tallow,  and  is  an  odorless  transparent 
syrup.  It  is  soluble  in  HO  and  alcohol.  Its  healing 
properties  are  remarkable,  and  its  use  is  common  in 
dressing  sores,  insect  bites,  chapped  hands,  etc. 
When  highly  heated  it  is  decomposed,  and  produces 
an  acrid  substance  (acroleine)  with  which  we  are 
familiar  in  the  disagreeable  smell  of  a  smouldering 
candle-wick  and  burning  fat. 

By  the  action  of  NO5  and  SO3  glycerin  is  con- 
verted into  nitro-glycerin,  an  oil  that  explodes  with 
most  fearful  violence  by  the  slightest  concussion,  or 
even  from  unexplainable  causes.  It  is  used  in 
blasting. 

LYE  is  a  strong  solution  of  KO,  and  is  obtained, 
as  we  have  seen,  by  leaching  ashes.  The  alkali  is 
contained  in  the  ashes  in  the  form  of  KO.CO2.  At 
the  bottom  of  the  leach-tub  a  little  lime  is  commonly 


THE   FIXED   OILS.  185 

placed  to  absorb  the  C02  and  leave  the  KO  unneutral- 
ized  by  the  acid,  and  therefore  stronger. 

HOME-MADE  SOAPS  are  formed  by  heating  "  lye" 
and  "  soap-grease."  In  this  process  the  potassa  of 
the  lye  drives  off  the  glycerin  of  the  grease  and 
makes  new  salts  which  contain  KO,  instead  of  gly- 
cerin, as  the  base ;  thus : 

Stearic  acid,  )  x   (  Stearate  of  potassa. 

T. ,  /  with  Potassa  (as  a  base),  \  ,. 

Marganc  "      V  "  •{  Margarate  of  " 

Oleic        «     j  cbangeto  (oieateof       " 

These  three  salts  constitute  soap.  The  expelled  gly- 
cerin remains  floating  around  alone  through  the 
mass.  This  soap  is  soft  because  of  the  attraction 
of  KO  for  HO.  The  boiling  merely  hastens  the 
chemical  change.  It  takes  place  more  slowly  in  the 
making  of  "  cold  soap." 

HARD  SOAP  contains  soda  instead  of  KO  as  a  base. 
This  is  not  deliquescent,*  and  so  the  soap  retains  its 
solid  form.  Soda  soap  can  be  formed  from  potassa 
soap  by  the  addition  of  common  salt  (NaCl). 

Reaction. — The  O  of  the  potassa  (KO)  unites  with 
the  sodium  (Na)  of  the  salt  (NaCl),  forming  soda 
(NaO).  The  chlorine  (Cl)  of  the  salt  (NaCl)  unites 
with  the  potassium  (K)  of  the  potassa  (KO),  forming 
chloride  of  potassium  (KC1).  The  soda  thus  formed 
displaces  the  potassa,  and  makes  a  hard  or  soda 

*  A  deliquescent  body  is  one  that  dissolves  in  HO,  which  it 
absorbs  from  the  air. 


186  ELEMENTARY  CHEMISTRY. 

soap,  while  the  KC1  remains  dissolved  in  the  water ; 
thus : 


Stearate  of     \      KO        NaCl      (  Stearate  of  soda. 
Margarate  of  v  =  •<  Margarate  of  soc 

Oleate  of        J     NaCl  .     NaO      (  Oleate  of  soda. 


The  kind  of  fat  used,  by  the  amount  of  olein  it  con- 
tains, also  determines  the  softness  of  the  soap.  Ex. : 
Tallow  makes  a  harder  soap  than  lard,  since  it  has 
less  olein.  Soap  has  a  powerful  affinity  for  HO,  and 
will  readily  absorb  50  per  cent,  of  its  weight.  It  is 
therefore  noticeable  that  dealers  commonly  keep 
their  soaps  in  cellars  or  damp  places.  The  best  old 
soap  contains  at  least  20  per  cent. 

FANCY  SOAPS. — Castile  soap  is  composed  of  olive- 
oil  and  soda.  Its  mottled  appearance  is  caused  by 
oxyd  of  iron,  which  is  stirred  through  it  in  fanciful 
designs  while  it  is  yet  soft.  Yellow  soaps  contain 
rosin  in  part,  instead  of  fat,  forming  a  rosin  soap. 
Cocoanut-oil  makes  a  soap  which  will  dissolve  in  salt 
water,  and  is  therefore  used  at  sea.  It  also  forms  a 
strong  lather,  and  is  sold  as  "  shaving-soap."  Wash- 
ing fluids  contain  an  unusual  amount  of  alkali,  and 
are  therefore  apt  to  be  injurious  to  the  cloth.  Soap- 
balls  are  made  by  dissolving  soap  in  a  very  little 
water,  and  then  working  it  with  starch  to  a  proper 
consistency  to  be  shaped  into  balls.  White  toilet- 
soaps  are  made  from  lard  and  soda. 

SOAP  IN  HARD  WATER. — Water  containing  any  min- 
eral matter  will  not  dissolve  soap,  since  the  lime, 


THE  FIXED   OILS.  187 

magnesia,  etc.,  displace  the  alkali  in  the  soap,  and 
form  a  new  soap  which  is  not  soluble,  but  floats  on 
top  as  a  greasy  scum.  Example :  A  potassa  soap  in 
lime-water  changes  to  a  lime  soap.  Thus — 

Stearate  of        ^  /  Stearate  of        \ 

Mar^arate  of     >  KO,  changes  to   •<  Margarate  of     j-  CaO. 
Oleate  of  '  '  Oleate  of  ) 


THE  CLEANSING  QUALITIES  OF  SOAP. — There  exudes 
constantly  from  the  pores  of  our  skin  an  oily  per- 
spiration, and  this,  catching  the  floating  dust,  dries 
into  a  film  of  greasy  dirt  which  will  not  dissolve 
in  water.  The  alkali  of  soap  combines  with  this 
oily  substance  and  makes  a  soap  of  it,  which  is 
soluble.  In  addition  to  this  the  alkali  also  dis- 
solves thi3  cuticle  of  our  skin,  and  thus  produces 
the  "  soapjr  feeling,"  as  we  term  it,  when  we  handle 
soap. 

SOAPSUDS  consists  of  a  thin  film  of  soap  filled  with 
bubbles  of  air.  It  is  an  excellent  remedy  in  almost 
all  cases  of  poisoning,  and  where  the  exact  antidote 
is  not  at  hand  should  be  taken  immediately.  Soap- 
bubbles  are  said  to  be  only  two-millionths  of  an 
inch  in  thickness. — (Newton.)  They  are  thinnest  at 
the  top,  as  the  water  runs  down  the  sides  toward 
the  bottom  constantly.  These  falling  films  of  water 
cause  the  refraction  of  light,  and  a  beautiful  play  of 
colors. 

ADULTERATION. — Soap  is  frequently  contaminated 


188  ELEMENTABY  CHEMISTBY. 

with  gypsum,  lime,  pipe-clay,  etc.  These  may  be 
detected  by  dissolving  a  small  piece  in  alcohol  and 
noticing  if  there  be  any  precipitate. 

CANDLES  are  made  from  tallow,  stearin,  paraffine, 
wax,  spermaceti,  etc.  Tallow  candles  and  their 
manufacture  are  too  well  known  to  need  description. 
Stearin  or  adamantine  candles  are  moulded  like  or- 
dinary candles.  They  are  prepared  from  tallow  or 
lard,  which  is  first  boiled  with  lime  and  so  made 
into  a  soap.  This  soap  is  decomposed  by  sulphuric 
acid,  which  takes  away  the  lime,  forming  sulphate  of 
lime,  which,  being  insoluble,  sinks  to  the  bottom, 
leaving  the  three  acids  of  the  fat  floating  upon  the 
surface.  The  glycerin  is  also  left  by  itself  in  the 
liquid,  from  whence  it  is  removed  and  prepared  for 
the  market.  The  acids,  when  cool,  are  subjected  to 
great  pressure ;  the  olein  flows  out,  leaving  the 
stearic  and  margaric  acids  as  a  milk-white,  odorless, 
tasteless  solid,  which  is  commonly  called  stearin, 
since  that  acid  is  the  principal  constituent.  Paraf- 
fine candles  are  made  from  coal-oil,  as  we  have  al- 
ready described.  Wax  candles  are  manufactured  by 
the  following  process.  A  large  number  of  cotton 
wicks  are  hung  upon  a  revolving  frame  with  project- 
ing arms.  The  wicks  are  fitted  at  the  end  with 
metal  tags  to  keep  the  wax  from  covering  that  part. 
As  the  machine  slowly  turns,  a  man,  standing  ready 
with  a  vessel  of  melted  wax,  carefully  pours  a  little 
down  each  wick  in  succession.  This  process  con- 
tinues until  the  candles  are  fed  to  the  desired  size. 


THE  FIXED  OILS.  189 

They  are  then  well  rolled  on  a  smooth  stone  slab, 
the  tops  cut  by  conical  tubes,  the  bottoms  trimmed, 
and  they  are  ready  for  use.  The  large  tapers  burned 
in  Catholic  cathedrals  are  made  by  placing  the  wick 
on  a  sheet  of  wax,  rolling  it  up  till  the  right  thick- 
ness is  reached,  when  the  candle  is  trimmed  and 
polished  as  before. 

Spermaceti  candles  are  run  from  the  white  crystal- 
line solid  fat  which  is  found  with  sperm  oil  in  the 
head  of  the  sperm  whale. 

WAX  is  found  in  nearly  all  plants.  It  forms  the 
shiny  coating  of  the  leaves  and  fruit.  Example : 
Lemon  leaf,  apple.  Certain  plants  in  Japan  contain 
so  much  wax  that  it  is  separated  by  boiling  and 
used  for  making  candles.  Bees  gather  the  wax  for 
the  construction  of  their  comb  partly  from  flowers, 
and  a  part  they  manufacture  from  the  sweet  juices 
sipped  from  the  flowers.  Yellow  beeswax  is  bleached 
by  exposure  in  thin  ribbons  to  the  air. 

LINSEED  OIL  is  a  drying  oil,  as  it  is  termed — i.  e.,  it 
absorbs  O  from  the  air,  and  hardens  by  exposure. 
It  is  expressed  from  flaxseed,  which  furnishes  about 
one-fifth  of  its  own  weight  of  oil.  Soiled  oil  is  made 
by  boiling  the  crude  oil  with  litharge  (PbO)  for 
several  hours.  The  oxyd  of  lead  combines  with  the 
gummy  mucilage  of  the  oil,  which  collects  as  a  slimy 
sediment.  Linseed  oil  is  used  in  mixing  paints  and 
varnishes.  Putty  consists  of  linseed  oil  and  chalk 
( Whiting)  well  mixed.  Printers'  ink  is  made  by  burn- 
ing linseed  oil  until  it  becomes  thick  and  viscid, 


190  ELEMENTARY  CHEMISTRY. 

when  lampblack  is  stirred  in,  to  make  it  of  the 
proper  consistency. 

COD  LITER  OIL  is  extracted  from  the  liver  of  the 
codfish.  It  contains  I,  Br,  and  P,  and  is  much 
used  as  a  remedy  in  Consumption. 

CROTON  OIL  is  made  from  the  seeds  of  an  Indian 
plant ;  and  is  used  as  a  powerful  purgative  and  for 
causing  eruptions  on  the  skin. 

CASTOR  OIL  is  extracted  from  the  castor-oil  bean. 
It  is  used  as  a  purgative,  and  also  in  perfumery  and 
hair-oils. 

SWEET-OIL,  OR  OLIVE-OIL,  is  an  unctuous  oil,  L  e.,  it 
absorbs  O  on  exposure  to  the  air — not  hardening 
like  the  drying  oils,  but  remaining  sticky,  and  after 
a  time  becoming  rancid  from  the  formation  of  dis- 
agreeable volatile  acids.  Sweet-oil  is  expressed 
from  the  olive  fruit.  In  Europe  it  is  extensive- 
ly used  instead  of^butter.  It  is  employed  as  a 
machine-oil,  although  the  coal-oils  are  now  much 
preferred. 

VOLATILE  OILS. 

The  Volatile  oils,  unlike  the  Fixed,  make  no  soaps, 
and  dissolve  readily  in  alcohol  or  ether.  Their  so- 
lution in  alcohol  forms  an  essence,  hence  the  term 
"  essential,"  by  which  they  are  frequently  called. 

Source. — They  are  principally  of  vegetable  origin. 
They  are  found  in  the  petals  of  a  flower,  as  the 
violet ;  in  the  seed,  as  caraway ;  in  the  leaves,  as 
mint ;  in  the  root,  as  sassafras ;  and  sometimes 


VOLATILE   OILS.  191 

several  kinds  of  oil  are  obtained  from  different  parts 
of  the  same  plant.  Example :  The  flower,  leaves, 
and  rind  of  the  orange-tree  furnish  each  its  own 
variety.  The  perfume  of  flowers  is  produced  by 
these  volatile  oils  ;  but  how  slight  a  quantity  is 
present  may  be  inferred  from  the  fact  tha/t  one 
hundred  pounds  of  fresh  roses  will  give  scarcely  a 
quarter  of  an  ounce  of  Attar  of  Roses. 

Preparation. — In  the  peppermint,  the  wintergreen, 
and  many  others  the  plant  is  distilled  with  water. 
The  oils  pass  over  with  the  steam,  and  are  con- 
densed in  a  refrigerator  connected  with  the  "  Mint 
Still."  The  oil  floats  on  the  surface  of  the  con- 
densed water,  and  may  be  removed.  A  small  por- 
tion, however,  remains  mingled  with  the  latter, 
which  thus  acquires  its  pecuUar  taste  and  odor, 
constituting  what  are  termed  "perfumed  waters." 
Example  :  Rose-water,  peppermint-water.  In  some 
flowers,  as  the  violet,  jasmin,  etc.,  the  perfume  is  too 
delicate  to  be  collected  in  this  manner.  They  are 
therefore  laid  between  woollen  cloths  saturated  with 
some  fixed  oil.  This  absorbs  the  essential  oil,  which 
is  then  dissolved  by  alcohol.  Oil  of  lemon  is  ob- 
tained from  the  rind  of  the  fruit  by  expression  or  by 
digesting  in  alcohol.  Example  :  A  good  essence  is 
made  by  putting  bits  of  lemon-peel  in  a  bottle  of 
alcohol. 

COMPOSITION. — CJi^  is  the  common  symbol  of  a 
large  number  of  these  oils.  Thus  the  oils  of  lemon, 
jumper,  citron,  black  pepper,  copaiba,  bergamot, 


192  ELEMENTARY  CHEMISTRY. 

turpentine,  cubebs,  and  oranges,  are  isomeric.  A 
second  class  contains,  besides  C  and  H,  a  little  O ;  a 
third,  in  addition,  has  S. 

FIRST  CLASS  OF  VOLATILE  OILS. — Turpentine  is  a 
type  of  this  division.  It  is  made  by  distilling  pitch 
with  HO.  It  is  generally  called  spirits  of  turpen- 
tine. It  is  highly  inflammable,  and,  owing  to  the  ex- 
cess of  C,  burns  with  a  great  smoke.  By  the  union 
of  an  atom  of  its  H  with  an  atom  of  the  O  of  the 
air  to  form  HO,  it  is  converted  into  rosin.  In  this 
way,  when  exposed  in  bottles  half  full,  the  turpen- 
tine around  the  nozzle  becomes  first  sticky  and  then 
resinous.  Old  oil  should  not  be  taken  to  remove 
grease  spots,  as,  while  it  will  remove  one,  it  will 
leave  another  of  its  own.  Camphene  is  turpentine 
purified  by  repeated  distillation.  Burning-fluid  is 
a  mixture  of  camphene  and  alcohol.  In  the  heat  of 
the  burning  H  of  the  latter,  the  C  of  the  former  is 
consumed,  and  this  produces  a  bright  light.  The 
tendency  of  camphene  to  smoke  is  thus  diminished, 
and  the  illuminating  power  increased.  By  the  ac- 
tion of  HC1  on  turpentine  or  oil  of  lemons  an  arti- 
ficial camphor  is  produced  very  nearly  resembling 
our  common  camphor. 

THE  SECOND  CLASS  includes  the  oils  of  bitter  al- 
monds, cinnamon,  peppermint,  roses,  lavender,  etc. 
They  are  sometimes  called  "  The  Camphors,"  because 
of  their  general  resemblance  to  the  crystalline  essence 
known  by  that  name.  Camphor  (C6H4O2)  is  obtained 
by  distilling  the  roots  and  loaves  of  the  camphor- 


BESINS  AND  BALSAMS.  193 

tree  of  Japan  in  water,  and  condensing  the  vapors 
in  rice-straw.  It  is  purified  by  sublimation.  When 
kept  in  a  bottle,  it  vaporizes,  and  its  delicate  crystals 
collect  on  the  side  toward  the  light.  Taken  internal- 
ly, except  in  small  doses,  it  is  a  virulent  poison.  Its 
solution  in  alcohol  is  called  spirits  of  camphor.  If 
HO  be  added  to  this,  the  camphor  will  be  precipita- 
ted as  a  flour-like  powder. 

THE  THIRD  CLASS  contains  S,  and  sometimes  N. 
It  includes  garlic,  assafcetida,  hops,  onions,  mustard, 
horseradish,  etc.  They  are  known  for  their  pun- 
gent taste  and  the  disagreeable  odor  they  often  im- 
part to  the  breath.  The  oil  of  mustard  is  not  con- 
tained in  the  seed,  but  is  formed  in  it  by  the  action 
of  water  and  a  latent  ferment.  This  is  the  reason 
why  mustard,  when  first  prepared  for  the  table,  is 
bitter,  but  becomes  pungent  after  a  little  time. 


BESINS  AND  BALSAMS. 

Kesins  are  formed  from  the  essential  oils  by  oxy- 
dation.  Example :  Turpentine^  as  we  have  just 
seen,  is  changed  to  rosin,  a  resinous  substance.  If 
the  resin  is  dissolved  in  some  essential  oil  it  is 
called  a  balsam.  Example  :  Pitch  is  a  true  balsam, 
since  by  distillation  it  is  separated  into  rosin  and 
turpentine. 

9 


194 


ELEMENTARY   CHEMISTRY. 


Source. — They  mostly  exude  from  incisions  in 
trees  and  shrubs,  in  the  form  of  a  balsam,  which 
oxydizes  on  exposure  to  the  air,  and  becomes  a  resin. 
Example  :  Common  plum-tree,  pine-tree. 

Properties  of  Resins.-^-Thvy  are  translucent,  brittle, 
insoluble  in  HO,  but  soluble  in  ether,  alcohol,  or  any 
volatile  oil,  are  non-conductors  of  electricity,  and 
burn  with  much  smoke.  They  do  not  decay,  and, 
indeed,  have  the  power  of  preserving  other  sub- 
stances. For  this  reason  they  were  used  in  em- 
balming the  bodies  of  the  ancient  Egyptians,  which, 
after  the  lapse  of  two  thousand  years,  are  yet  found 
dried  into  mummies  in  their  mammoth  tombs — the 
Pyramids. 

ROSIN  constitutes  about  75  per  cent  of  pitch.  It 
is  used  in  making  soaps,  to  increase  friction  in  violin 
bows  and  the  cords  of  clock-weights,  in  soldering, 
and  as  a  source  of  illuminating  gas.  Shoemakers' 
wax  is  made  by  burning  rosin  until  partly  charred. 

LAC  exudes  from  the  ficus-tree  of  the  East  Indies. 
An  insect  punctures  the  bark,  and  the  juice  flows 
out  over  the  insect,  which  works  it  into  cells  in 
which  to  deposit  its  eggs.  The  twigs  incrusted  with 
the  dried  gum  is  called  stick-lac,  when  removed  from 
the  wood  it  is  seed-lac,  when  melted  and  strained, 
shellac.  The  liquefied  resin  is  dropped  upon  large 
leaves,  and  so  cools  in  broad  thin  pieces,  as  we  buy 
it.  Sealing-wax  is  made  of  shellac  and  turpentine ; 
vermilion  is  added  to  give  the  red  color.  Shellac  is 
much  used  in  making  varnishes.  * 


RESINS  AND  BALSAMS.  195 

GUM  BENZOIN  also  exudes  from  a  tree  in  the  East 
Indies.  It  contains  benzoic  acid.  It  is  used  in 
fumigation,  in  cosmetics,  and  on  account  of  its  fra- 
grant odor  is  burnt  as  incense.  Ex. :  Place  some 
green  sprigs  under  a  glass  receiver,  and  at  the  bot- 
tom a  hot  ^iron,  on  which  sprinkle  a  little  benzoic 
acid.  It  will  sublime  and  collect  in  beautifully  deli- 
cate crystals  on  the  green  leaves  above,  making  a 
perfect  illustration  of  winter  frost-work. 

AMBER  is  a  fossil  resin  which  has  exuded  in  some 
past  age  of  the  world's  history  from  trees  now  ex- 
tinct. It  is  sometimes  found  containing  various  in- 
sects perfectly  preserved,  which  were  without  doubt 
entangled  in  the  mass  while  it  was  yet  soft.  These 
are  so  beautifully  embalmed  in  this  transparent  glass 
that  they  give  us  a  good  idea  of  the  insect  life  of 
that  age.  It  is  cast  up  by  the  sea,  in  pieces  of  a  few 
ounces  each,  on  the  shores  of  the  Baltic  and  off  the 
coast  of  New  Jersey.  It  is  commonly  translucent, 
and  susceptible  of  a  high  polish.  It  is  used  for  or- 
naments, mouth-pieces,  necklaces,  buttons,  etc.  It 
is  a  prominent  ingredient  in  carriage  varnish. 

CAOUTCHOUC  or  INDIA-RUBBER  is  a  pure  hydro- 
carbon, and  may  be  considered  as  hardened  illumi- 
nating gas.  It  exudes  from  certain  trees  in  South 
America  as  a  milky  juice.  The  globules  of  rubber 
are  suspended  in  it  as  butter  is  in  milk.  By  adding 
ammonia  the  sap  may  be  kept  unchanged  for  months, 
and  is  sometimes  exported  in  that  form  preserved  in 
tighfly  corked  bottles.  The  tree,  it  is  said,  yields 


196  ELEMENTARY  CHEMISTRY. 

about  a  gill  per  day  from  each  incision  made.  A 
little  clay  cup  is  placed  underneath,  from  which  the 
juice  is  collected  and  poured  over  clay  or  wooden 
patterns  in  successive  layers  as  it  dries.  To  hasten 
the  process  it  is  carried  on  over  large  open  fires,  the 
smoke  of  which  gives  to  the  rubber  its  black  color  ; 
when  pure  it  is  almost  white.  When  nearly  hard 
the  rubber  will  receive  any  fanciful  design  which 
may  be  marked  upon  it  with  a  pointed  stick.  The 
natives  often  form  the  clay  into  odd  shapes  as  bot- 
tles, images,  etc.,  and  the  rubber  is  sometimes  ex- 
ported in  these  uncouth  forms.  The  solvents  of 
rubber  are  ether,  naphtha,  coal-oil,  turpentine,  ben- 
zole, etc.  It  melts,  but  does  not  become  solid  on 
cooling.  It  loses  its  elastic  power  when  stretched 
for  a  long  time,  but  recovers  it  on  being  heated.  In 
the  manufacture  of  rubber  goods  for  suspenders,  etc., 
the  rubber  thread  is  drawn  over  bobbins  and  left 
for  some  days  until  it  becomes  inelastic.  In  this 
state  it  is  woven,  after  which  a  hot  wheel  is  rolled 
over  the  cloth  to  restore  the  elasticity. 

VULCANIZED  RUBBER  is  made  by  heating  caout- 
chouc with  a  small  amount  of  sulphur.  This  con- 
stituted Goodyear's  original  patent,  and  was  dis- 
covered accidentally.  While  engaged  in  experi- 
menting upon  improvements  in  this  branch  of  manu- 
facture, he  was  one  day  talking  with  a  friend  and 
happened  to  drop  a  bit  of  sulphur  in  a  pot  of  melted 
rubber.  By  one  of  those  happy  intu:tions  which 
seem  to  come  only  to  men  of  genius,  he  watched  tho 


ORGANIC  BASES.  197 

result,  and  discovered — "  Vulcanized  Eubber !"  It 
is  less  liable  to  be  hardened  by  cold  or  softened  by 
heat,  and  admits  of  many  uses  to  which  common 
rubber  would  be  entirely  unsuited.  When,  in  addi- 
tion, it  is  mixed  with  pitch  and  magnesia,  it  becomes 
a  hard  brittle  solid,  capable  of  a  high  polish,  and  is 
used  for  knife-handles,  combs,  and  brushes. 

GUTTA-PERCHA  resembles  caoutchouc  in  its  source, 
preparation,  and  appearance.  It  softens  in  warm 
water,  and  can  then  be  moulded  into  any  desired 
shape.  When  cooled  it  assumes  its  original  solidity. 
It  is  extensively  used  in  taking  impressions  of  medals, 
etc. 


ORGANIC  BASES 

The  organic  bases,  or  alkaloids,  as  they  are  called, 
are  the  bases  of  true  salts  found  in  plants.  They 
dissolve  slightly  in  HO,  but  freely  in  alcohol.  They 
have  a  bitter  taste,  and  rank  among  the  most  fearful 
poisons  known.  The  antidote  is  tannin,  which  forms 
with  them  insoluble  tannates.  Any  liquid  contain- 
ing it  is  of  value — as  strong  green  tea — and  should 
be  immediately  administered  in  a  case  of  poisoning 
by  any  of  the  alkaloids. 

OPIUM  is  the  dried  juice  of  the  poppy  plant,  which 
is  extensively  cultivated  in  Turkey  for  the  sake  of  .this 
product.  Workmen  pass  along  the  rows  soon  after 


198  ELEMENTARY  CHEMISTRY. 

the  flowers  have  fallen  off,  cutting  slightly  each  cap- 
sule. From  this  incision  a  milky  juice  exudes  and 
collects  into  a  little  tear.  In  twenty-four  hours  these 
are  gathered  and  beaten  up  in  an  earthen  jar  with 
saliva  to  the  proper  consistency,  when  the  mass  is 
wrapped  in  leaves  for  the  market.  It  is  afterward 
purified. 

Properties. — Opium  produces  a  powerful  influence 
on  the  nervous  system.  It  stimulates  the  brain  and 
excites  the  imagination  to  a  wonderful  pitch  of  in- 
tensity. The  dreams  of  the  opium-eater  are  said  to 
be  vivid  and  fantastic  beyond  description.*  The  dose 
must  be  gradually  increased  to  repeat  the  effect,  and 
the  result  is  most  disastrous.  The  nervous  system 
becomes  deranged,  and  no  relief  can  be  secured  save 
by  a  fresh  resort  to  this  baneful  drug.  Labor  be- 
comes irksome,  ordinary  food  distasteful,  and  racking 
pains  torment  the  whole  body.  No  person  can  be 
too  careful  in  the  use  of  a  narcotic  whose  influence 
is  liable  to.  become  so  destructive. 

OPIUM-SMOKING. — In  China  the  custom  of  smoking 
opium  is  fearfully  prevalent.  The  opium  is  made 
into  a  thick  syrup  with  water.  A  small  portion  is 
placed  in  the  bowl  of  the  pipe,  which  is  held  in  the 
flame  of  an  oil-lamp  until  the  opium  is  partly  vola- 
tilized and  fully  ignited.  During  this  process,  the 
smoker,  reclining  upon  his  side,  gently  inhales  the 
fumes,  and  absorbs  them  by  retaining  them  until 
they  slowly  pass  out  through  the  nose.  Opium-shops 


OBGANIC  BASES.  199 

are  said  to  be  more  numerous  in  China  than  even 
rice-shops.  The  effect  is  worse  than  that  of  intoxi- 
cating liquors,  if  it  is  possible  to  compare  two  such 
fearfully  pernicious  vices. 

MORPHIA. — Morphine  is  one  of  the  alkaloid  bases 
of  opium.  It  is  so  called  from  Morpheus,  the  god 
of  sleep.  It  is  a  bitter,  narcotic,  resinous-like  sub- 
stance. It  is  used  principally  as  a  sulphate  of  mor- 
phia, in  doses  of  one-eighth  to  one-fourth  of  a  grain, 
to  alleviate  pain  and  produce  sleep.  Laudanum  is 
the  tincture  of  opium.  Paregoric  is  a  camphorated 
tincture  of  opium,  with  benzoic  acid  and  oil  of 
anise. 

QUINIA.—  Quinine  is  prepared  from  Peruvian  bark. 
It  is  employed  in  medicine  as  a  tincture  of  Peruvian 
bark,  or  in  the  form  of  sulphate  of  quinia,  for  cases 
of  fever  and  ague  and  all  periodic  diseases. 

NICOTINE  is  the  active  principle  of  the  tobacco 
plant.  It  is  volatile,  and  passes  off  in  the  smoke. 
A  drop  will  kill  a  large  dog.  It  probably  produces 
the  ill  effects  that  follow  the  use  of  tobacco. 

STRYCHNIA. — Strichnine  is  prepared  from  the  nux 
vomica  bean,  obtained  from  a  small  tree  in  the  East 
Indies.  The  "woorara,"  with  which  the  South 
American  Indians  poison  their  arrows,  is  a  variety 
of  strychnine.  This  is  so  deadly  that  the  scratch  of 
a  needle  dipped  in  it  would  produce  death.  Strych- 
nine is  scarcely  soluble  in  water,  but  freely  in  the 
essential  oils  and  chloroform.  It  is  so  intensely 
bitter  that  one  grain  will  impart  a  flavor  to  twenty- 


200  ELEMENTARY  CHEMISTRY. 

five  gallons  of  water.  One-thirtieth  of  a  grain  has 
killed  a  dog  in  thirty  seconds,  while  half  a  grain  is 
fatal  to  a  man. 

The  Chromatic  Test  consists  in  placing  on  a  clean 
porcelain  plate  a  drop  of  the  suspected  liquid,  a  drop 
of  SO3,  and  a  crystal  of  bichromate  of  potassa.  Mix 
the  three  very  slowly  with  a  clean  glass  rod.  If  there 
be  any  strychnine  present,  it  will  change  the  color 
into  a  beautiful  violet  tint,  passing  into  a  pale  rose. 
It  is,  however,  one  of  the  most  difficult  poisons  to 
detect.  Arsenic  was  formerly  used  by  the  poisoner, 
but  Marsh's  test  infallibly  reveals  its  presence  in  the 
body  of  the  victim,  even  after  many  years  have 
elapsed.  But  the  organic  poisons  are  so  easily  acted 
upon  by  the  fluids  of  the  system,  that  in  one  case, 
though  four  grains  were  taken,  and  death  ensued 
very  quickly,  yet  the  "  chromatic  test"  failed  to  re- 
veal the  presence  of  any  strychnine  in  the  stomach. 
However,  the  murderer  is  not  to  escape.  This  is 
the  only  poison  except  brucite  (and  that  also  is  ex- 
tracted from  nux  vomica)  that  produces  tetanus  or 
lock-jaw.  This  symptom  infallibly  proves  to  the 
physician  that  death  has  been  caused  by  strychnine. 
To  prove  this  conclusively,  a  tiny  frog  is  brought  into 
the  court-room  and  made  to  show  the  effects  of  the 
poison.  So  sensitive  is  this  gentle  reptile,  that  a  few 
drops  of  oil  containing  only  yo-o.V  or  °^  a  g1*^  will 
instantly  throw  him  into  the  most  rigid  locked-jaw, 
in  which  he  is  incapable  of  producing  a  single  croak. 

COFFEINE  AND  THEiNE  constitute  the  active  prin- 


ORGANIC  BASES.  201 

ciple  of  tea  and  coffee,  and  are  isomeric.  They  crys- 
tallize in  beautiful  white  prisms  of  a  silky  lustre.  In 
addition,  tea  contains  from  12  to  18  per  cent,  of  tannic 
acid,  some  15  per  cent,  of  gluten,  which  is  lost  in  the 
"  grounds"  (unless  we  imitate  the  Japanese  and  eat 
them  with  the  tea),  and  a  volatile  oil  which  gives  to 
it  its  peculiar  aromatic  odor  and  taste.  Coffee  con- 
tains 14  per  cent,  of  a  fixed  oil,  and  also  an  essential 
oil  which  is  developed  in  roasting,  and  is  remarkably 
volatile,  so  that  it  soon  escapes  unless  the  coffee  is 
kept  tightly  covered. 

Tea-raising. — The  tea-plants  are  allowed  to  grow 
only  about  a  foot  and  a  half  high,  and  resemble  in 
some  respects  the  low  whortleberry  bush.  They  are 
grown  in  rows,  three  to  five  in  a  hill,  very  much  as 
corn  is  with  us.  The  medium-sized  leaves  are  picked 
by  hand,  the  largest  ones  being  left  on  the  bushes  to 
favor  their  growth.  Each  little  hill  or  clump  will 
furnish  from  three  to  five  ounces  of  green  leaves, 
or  about  one  ounce  of  tea  in  the  course  of  the  sea- 
son. The  leaves  are  first  wilted  in  the  sun,  then 
trodden  in  baskets  by  barefooted  men  to  break  the 
stems,  next  rolled  by  the  hands  into  a  spiral  shape, 
then  left  in  a  heap  to  heat  again,  and  finally  dried 
for  the  market.  This  constitutes  BLACK  TEA,  and  the 
color  would  be  produced  in  any  leaves  left  thus  to 
wilt  and  heat  in  heaps  in  the  open  air.  The  Chinese 
always  drink  this  kind  of  tea.  They  use  no  milk  or 
sugar,  and  prepare  it,  not  by  steeping,  but  by  pour- 
ing hot  water  on  the  tea  and  allowing  it 'to  stand  for 


202  ELEMENTABY  CHEMISTRY. 

a  few  minutes.  Whenever  a  friend  calls  on  a  China- 
man, common  politeness  requires  that  a  cup  of  tea 
be  immediately  offered  him. 

Green  Tea  is  prepared  like  black,  except  that  it  is 
not  allowed  to  wilt  or  heat,  and  is  quickly  dried  over 
a  fire.  It  is  also  very  frequently,  if  not  always,  col- 
ored, cheap  black  teas  and  leaves  of  other  plants 
being  added  in  large  quantities.  In  this  country, 
damaged  teas  and  the  "  grounds"  left  at  hotels  are 
re-rolled,  highly  colored,  packed  in  old  tea-chests, 
and  sent  out  as  new  teas.  Certain  varieties  of  black 
tea  even  receive  a  coating  of  black-lead  to  make 
them  shiny. 

There  are  various  other  alkaloids  that  are  worthy 
of  mention  merely.  Lettuce  contains  one  similar  to 
opium,  which  gives  it  a  slight  narcotic  influence. 
Aconite  is  obtained  from  monk's-hood,  veratrine 
from  the  hellebore,  solanine  from  the  henbane,  pi- 
perine  from  white,  black,  and  long  peppers — isomeric 
in  white  needle-shaped  crystals. 

ORGANIC  COLORING  PRINCIPLES. 

With  the  exception  of  cochineal,  all  the  organic 
coloring  principles  are  of  vegetable  origin.  The 
beautiful  tints  of  flowers  are  so  evanescent  that  they 
cannot  be  retained.  Coloring  matters  are  therefore 
taken  of  soberer  hue  from  the  interior  of  plants, 
where  they  are  less  exposed  to  the  light. 

DYEING. — Very  few  of  the  colors  have   such   an 


ORGANIC  COLORING  PRINCIPLES.  203 

affinity  for  the  fibres  of  the  cloth  that  they  will  not 
wash  out.  Such  as,  like  indigo,  will  dye  directly  are 
called  substantive  colors.  But  the  majority  require  a 
third  substance  which  has  an  attraction  for  both  the 
coloring  matter  and  the  cloth,  and  will  hold  them 
together.  Such  substances  are  called  mordants  (from 
mordeo,  to  bite),  because  they  bite  the  color  into  the 
cloth.  The  most  common  mordants  are  alum,  oxyd 
of  tin,  and  copperas.  In  dyeing,  the  cloth  is  first 
dipped  in  a  solution  of  the  mordant,  and  then  of  the 
dye-stuff.  Ex. :  If  a  piece  of  cotton  cloth  be  dipped 
in  a  decoction  of  madder,  it  will  receive  an  unstable 
dirty  red  color.  If,  however,  it  be  soaked  first  in  a 
solution  of  alum  and  sugar  of  lead  (PbO.A),  the 
acetate  of  alumina  will  be  formed  in  its  fibres,  and 
will  act  as  a  mordant.  Now  dip  it  into  the  same  dye, 
and  it  will  come  out  a  brilliant  red — a  "  fast  color." 
The  mordant,  by  means  of  a  stamp,  may  be  applied 
to  the  cloth  in  the  form  of  a  pattern,  and  when  it  is 
afterward  washed,  the  color  will  all  be  removed  ex- 
cept where  the  mordant  fixed  it  in  the  printed  figure. 
The  same  dye  will  produce  different  colors  by  a 
change  of  mordants.  Ex. :  Logwood  and  copperas 
will  dye  black ;  logwood  and  tin,  a  violet.  Madder 
will  dye  in  this  way  red,  purple,  yellow,  orange,  and 
brown.  This  principle  lies  at  the  basis  of  dyeing 
"prints." 

CALICO-PRINTING. — A  calico-printing  machine  is 
very  complex.  Tiie  cloth  passes  between  a  series  of 
rollers,  upon  which  the  corresponding,  mordant  is 


204  ELEMENTAEY  CHEMISTIiY. 

put,  as  ink  is  on  type.  A  single  machine  sometimes 
prints  from  twenty  sets  of  rollers  ;  yet  each  impres- 
sion follows  the  other  so  accurately,  that  when  the 
cloth  has  passed  through,  the  entire  pattern  is 
printed  upon  it  with  the  different  mordants  more 
perfectly  than  any  painter  could  do  it,  and  so 
rapidly  that  a  mile  of  cloth  has  been  printed  with 
four  mordants  in  an  hour.  The  cloth  when  it  leaves 
the  printing  machine,  though  stamped  with  the 
mordants  in  the  form  of  the  figure,  betrays  nothing 
of  the  real  design  until  after  being  dipped  in  the 
dye,  which  acting  on  the  different  mordants  brings 
out  the  desired  colors.  The  print  is  now  washed, 
glazed,  and  fitted  for  the  market. 

BED  AND  VIOLET  COLORING  SUBSTANCES. — Madder  is 
the  root  of  a  plant  found  in  the  East  Indies.  When 
first  dug  it  is  yellow,  but  by  exposure  to  the  air  it 
absorbs  O  and  becomes  red.  It  is  used  in  dyeing 
the  brilliant  Turkey-red.  Cochineal  is  an  insect  that 
preys  upon  a  species  of  cactus  in  Central  America. 
It  is  raised  in  large  plantations,  dried  between  hot 
iron  plates,  and  exported  as  an  article  of  commerce. 
It  yields  the  brightest  scarlet  and  purple  dyes.  The 
purple  of  which  we  read  in  ancient  writings  was  a 
secret  with  the  Tyrians.  King  Huram,  we  learn, 
sent  a  workman  to  Solomon  skilled  in  this  art.  The 
dye  was  obtained  from  a  shell-fish  that  was  found 
on  the  coast  of  Phoenicia.  Each  animal  yielded  a 
tiny  drop  of  the  precious  liquid.  A  yard  of  cloth 
dipped  twice  in  this  costly  dye  was  worth  $150. 


ORGANIC  COLORING  PRINCIPLES.  205 

Brazil-wood  furnishes  a  red  which  is  not  very  per- 
manent. It  is  used  for  making  red  ink.  Experiment : 
Boil  2  oz.  of  Brazil-wood  in  a  pint  of  HO  for  fif- 
teen minutes,  then  add  a  little  gum-arabic  and 
alum. 

BLUE  COLORING  SUBSTANCES. — The  indigo  of  com- 
merce is  obtained  from  a  bushy  plant  found  in  Asia. 
The  juice  is  colorless,  but  by  fermentation  for  some 
days,  in  vats  of  water,  a  yellow  substance  is  formed, 
which  by  exposure  to  the  air  absorbs  O,  and  changes 
to  a  deep  blue.  By  any  deoxydizing  agent  the  color 
of  indigo  may  be  removed  at  pleasure.  Example : 
Add  to  a  test-tube  of  boiling  HO,  colored  with  a 
solution  of  indigo,*  a  drop  of  NO5.  The  blue  color 
will  instantly  disappear.  Litmm  is  obtained  from 
certain  kinds  of  lichens,  which  grow  on  the  rocks 
along  the  coasts  of  France  and  England.  The  juice 
is  colorless,  like  the  other  dye-plants,  but  assumes 
a  rich  purple  blue  by  the  addition  of  ammonia 
(NH3). 

GREEN  COLORING  SUBSTANCE. — Leaf-green,  as  found 
in  plants,  is  a  waxy  substance,  containing  several 
coloring  matters.  It  seems  to  lie  in  the  cells  of  the 
leaf  in  minute  crystals,  and  to  be  formed  by  the 
action  of  the  sunbeam.  Plants  removed  from  a 
dark  cellar  to  the  open  air  grow  green  rapidly. 

*  To  make  this  solution,  mix  a  little  pulverized  indigo  into 
a  paste  with  SOs.  Let  it  stand  a  few  days,  then  add  HO  at 
pleasure. 


206  ELEMENTABY  CHEMISTRY. 


ALBUMINOUS  BODIES. 

The  Albuminous  bodies  differ  essentially  from 
any  yet  named.  They  are  far  more  complex  in  their 
structure,  contain  more  nitrogen,  and  do  not  crys- 
tallize. The  most  important  are — 

Albumen, 

Fibrin, 

Casein. 

These  are  isomeric,  and,  when  taken  into  the 
system,  are  all  changed  into  albumen  before  leaving 
the  stomach.  When  decomposed  by  an  alkali  they 
yield  a  white  inodorous  solid,  which  will  act  as  a 
base  and  form  salts.  This  is  called  "Protein" 
(proteuo,  I  am  first),  and  these  substances  them- 
selves are  termed  the  protein  compounds.  Their 
composition  is  very  complex,  as  may  be  seen  from 
the  following  table  given  by  Liebig : 

Albumen  of  blood ) 

Albumen  of  flesh (  C316HmO68Na7Sa. 

Fibrin  of  flesh ) 

Albumen  of  eggs C216HmOC8N87S,. 

Casein Ca88Haa8O,0NMSa. 

Fibrin  of  blood C998Haa8OMN40Sa. 

ALBUMEN. — Sources. — It  exists  nearly  pure  in  the 
whites  of  eggs — hence  the  name  (albus,  white)  ;  also 
in  the  serum — the  transparent  part  of  the  blood — 
and  the  juices  and  seeds  of  many  plants. 

Properties. — It  is  soluble  in  cold,  but  insoluble  in 


ALBUMINOUS  BODIES.  207 

hot  HO.  At  a  temperature  of  145°  F.  it  coagulates. 
This  change  we  always  see  in  the  cooking  of  eggs. 
Alcohol,  corrosive  sublimate,  acids,  creosote,  etc., 
have  the  power  to  coagulate  albumen.  In  cases  of 
poisoning  by  these  substances  it  is  therefore  a  valu- 
able antidote,  as  it  wraps  them  up  in  an  insoluble 
covering,  and  so  protects  the  stomach.  Albumen 
seems  to  have  the  properties  of  an  acid  and  a  base. 
It  coagulates  with  an  acid  by  uniting  with  it  as  a 
base.  It  coagulates  with  a  salt  by  uniting  with  its 
base  as  an  acid.  It  exists  in  two  amorphous  condi- 
tions— as  a  liquid  in  the  sap  of  plants,  the  humors 
of  the  eye,  serum  of  blood,  etc.;  as  a  solid  in  the 
seeds  of  plants  and  the  nerves  and  brains  of  ani- 
mals. 

Vegetable  Albumen. — If  the  water  used  in  making 
starch  from  potatoes  be  boiled,  it  will  become  tur- 
bid and  deposit  a  flaky  white  substance  identical 
with  the  whites  of  eggs,  and  therefore  named  vege- 
table albumen. 

FIBRIN  constitutes  chiefly  the  fibrous  portion  of 
the  muscles.     If  a  piece  of  lean  beef  be  washed  in 
clean  HO  until  all  the  red 
color  disappears,  the  mass 
of  white  tissue  which  will 
remain    is    called    fibrin. 
Like  albumen,  it  exists  in 
two  forms — as  a  liquid  in 
the  blood,  and  as  a  solid 

n      ,  ,       .,  ,  Fibrin,  or  Muscle. 

in    flesh    and    the    seeds 


203  ELEMENTARY  CHEMI8TEY. 

% 

of  plants.  The  clotting  of  blood  is  due  to  the  coagu- 
lation of  the  fibrin. 

Vegetable  Fibrin — Gluten. — If  wheat  flour  be  made 
into  a  dough,  and  then  kneaded  in  water  until  all 
the  soluble  portion  is  washed  away,  the  tough  glu- 
tinous mass  which  will  remain  is  called  gluten.  It 
is  identical  in  composition  with  fibrin,  and  is  there- 
fore named  vegetable  fibrin.  We  obtain  it  as  a  gum 
when  we  chew  wheat,  thereby  dissolving  the  starch. 
It  exists  most  abundantly  in  the  bran  of  cereal  grains. 
Example :  "Wheat. 

CASEIN  is  found  in  the  curd  of  milk  (whence  the 
name,  caseum,  cheese),  in  the  blood,  peas,  and  beans. 
The  curdling  of  milk  is  due  to  the  coagulation  of 
its  casein.  When  milk  sours,  its  lactic  acid  com- 
bines with  the  alkali  present,  and  precipitates  the 
casein,  which  is  only  soluble  in  HO  containing  some 
alkali.  The  rennet  (the  dried  stomach  of  a  calf), 
used  in  making  cheese,  acts  in  the  same  manner. 

Vegetable  Casein. — By  treating  peas  as  we  do  pota- 
toes in  forming  starch,  and  then  adding  a  little  acid 
to  the  water  which  is  left  after  the  starch  settles,  an 
albuminous  substance  is  deposited,  which  is  identical 
with  casein,  and  has  received  the  name  vegetable 
casein.  The  Chinese  use  it  largely  for  cheese. 

GELATIN. — Hot  water  dissolves  a  substance  from 
animal  membranes,  skin,  tendons,  and  bones,  which, 
on  cooling,  forms  a  yielding  tremulous  mass  called 
gelatin.  As  calves-foot  jelly,  soups,  etc.,  it  is  well 
known.  As  an  article  of  food  it  is  of  very  little  nu- 


ALBUMINOUS   BODIES.  209 

tritive  value.  It  may  answer  to  dilute  a  stronger 
diet,  but  of  itself  does  little  to  build  up  the  body  of 
an  invalid.  Beef-tea  is  by  far  more  strengthening 
than  jellies  or  blanc-mange.  Glue  is  a  gelatin  made 
from  bones,  hoofs,  horns,  etc.,  by  boiling  in  HO  and 
then  evaporating  the  solution.  Isinglass  is  the 
purest  gelatin,  and  is  obtained  from  the  air-bladders 
of  the  cod,  sturgeon,  and  other  fish.  Size  is  gelatin 
prepared  from  the  parings  of  parchment,  the  thin- 
nest kind  of  skins.  It  is  used  for  sizing  paper  to 
fill  up  the  pores  and  prevent  the  ink  fr,  m  spreading, 
as  it  does  on  unsized  or  blotting-paper. 

Vegetable  Gelatine  is  familiar  to  us  in  the  form  of 
blanc-mange  and  the  fruit-jellies.  It  is  nearly  like 
starch  or  grape-sugar  in  its  composition.  It  is 
called  Pectine  (see  page  159).  It  is  found  in  Ice- 
land moss,  grapes,  apples,  quinces,  and  other  fruits. 

MILK  is  a  natural  emulsion,  composed  of  exceed- 
ingly minute  globules  diffused  through  a  transparent 
liquid.  The  globules  consist  of  a  thin  envelope 
of  casein  filled  with  butter. 
Being  a  trifle  lighter  than  HO, 
they  rise  to  the  surface  as  cream. 
Churning  breaks  these  cover- 
ings, and  gathers  the  butter  in- 
to a  mass.  Milk  contains  some 
sugar,  and  this,  by  the  action  of  Milk  under  Microscope. 
the  O  of  the  air  changes  to  lactic  acid,  which  gives 
the  peculiar  taste  to  sour  milk.  The  casein  seems 
to  act  as  a  ferment  in  hastening  this  oxydation.  In 


210  ELEMENTAKY  CHEMISTRY. 

churning,  the  cream  always  "  turns,"  because  O  is 
rapidly  absorbed  as  the  milk  is  stirred,  and  lactic 
acid  formed.  Milk  sours  in  the  stomach  by  the 
action  of  the  acids,  which  convert  it  into  lactic 
acid. 

BONES  consist  of  organic  and  mineral  matter  com- 
bined. 

ANALYSIS.     (Berzelius.} 

Gelatin— (Gluten) 32.17 

Blood-vessels 1 . 13 

Phosphate  of  lime 51 .04 

Carbonate  of  lime 11 .30 

Fluoride  of  calcium 2 . 00 

Phosphate  of  magnesia 1.16 

Chloride  of  sodium  1 .20 

100.00 

By  soaking  a  bone  in  HC1  the  mineral  matters 
will  all  be  dissolved,  and  the  organic  matter  left  in 
the  original  shape  of  the  bone,  but  soft  and  pliable. 
If,  instead,  the  bone  be  burned  in  the  fire,  the 
organic  matter  will  be  removed  and  the  mineral 
left  white  and  porous.  The  blood  circulates  freely 
through  the  bones,  however  hard  they  may  seem  to 
be.  If  a  little  madder  be  mixed  with  the  food  of 
pigs,  it  will  tinge  red  all  their  bones.  If  the  madder 
be  given  at  considerable  intervals,  it  will  make 
streaks  of  white  and  red  bone  alternately. 

Putrefaction. — Owing  to  the  complex  structure  of 
albuminous  substances,  and  the  presence  of  the  fickle 


ALBUMINOUS  BODIES.  211 

nitrogen,  they  readily  oxydize  and  form  entirely 
new  compounds.  This  breaking  up  is  called  putre- 
faction. The  P  and  S  present  in  flesh  especially, 
take  up  the  H  in  hot  haste,  and  flying  off  as  sul- 
phuretted hydrogen  (HS)  and  phosphuretted  hydro- 
gen (PH3),  salute  our  olfactories  with  their  well- 
known  odors.  These  poisonous  and  offensive  gases 
abounding  near  slaughter-houses  and  similar  estab- 
lishments, make  them  so  unhealthy.  Any  portion 
of  an  albuminous  substance  thus  putrefying  may 
act  as  a  ferment.  This  probably  explains  the 
danger  physicians  incur  in  dissecting  a  dead  body. 
The  least  portion  of  the  decomposing  matter  enter- 
ing their  flesh,  through  a  scratch  even,  is  liable  to 
be  fatal.  The  presence  of  an  albuminous  substance 
always  hastens  decay.  The  white,  or  sap  wood, 
contains  some  N,  and  so  this  rots  very  quickly. 
Timber  steeped  in  a  solution  of  corrosive  sublimate 
(kyanized)  is  rendered  almost  indestructible,  because 
that  salt  coagulates  the  albumen.  The  absence  of 
HO  retards  chemical  change,  and  therefore  meats, 
apples,  etc.,  are  preserved  by  drying.  Salt  acts 
somewhat  in  the  same  way  by  absorbing  the  juice 
of  the  meat,  and,  while  it  covers  it  as  brine,  wards 
off  the  attacking  O  ;  but  as  it  dissolves  some  of  the 
salts  and  other  valuable  elements  of  the  meat,  it 
makes  it  less  nutritious. 


212  ELEMENTARY  CHEMISTBY. 


DOMESTIC  CHEMISTKY. 

In  the  chemistry  of  housekeeping  there  are  some 
points  not  yet  spoken  of,  and  they  may  now  be  prof- 
itably discussed. 

MAKING  BREAD. — Flour  consists  of  gluten,  starch, 
and  a  little  gum  and  sugar.  There  is  also  about  two 
per  cent,  of  ash,  about  one  half  of  which  is  phos- 
phate of  lime;  but  these  mineral  constituents  are 
found  mainly  in  the  bran.  In  mixing  the  "  sponge," 
the  process  is  purely  mechanical.  The  water  used 
moistens  the  starch,  dissolves  the  albumen,  sugar, 
and  gum,  and  causes  the  gluten  to  cohere.  When 
the  sponge  is  set  aside  in  a  warm  place  to  rise  (as 
heat  favors  chemical  change),  the  yeast,  yeast-cake, 
or  emptyings,  as  the  case  may  be,  induces  a  rapid 
fermentation,  converting  the  sugar  into  alcohol  and 
CO2.  This  gas  is  diffused  through  the  mass,  and 
struggles  to  escape,  but  is  retained  by  the  tenacious 
and  viscid  dough,  causing  it  to  "rise."  The  next 
step  includes  the  addition  of  fresh  flour,  and  a  la- 
borious process  of  "  kneading."  The  latter,  so  essen- 
tial to  good  bread,  diffuses  the  half-fermented  sponge 
uniformly  through  the  dough,  and  thus  spreads  the 
continued  fermentation  throughout  the  loaf ;  it  also 
breaks  up  into  smaller  ones  the  bubbles  of  gas  en- 
tangled in  the  gluten,  and  thereby  makes  the  bread 


DOMESTIC  CHEMISTRY.  213 

fine-grained.  The  dough  is  now  "moulded"  into 
loaves.  When  placed  in  the  hot  oven,  the  first  effect 
is  to  increase  the  fermentation.  Some  of  the  starch 
is  turned  into  sugar  to  supply  material,  the  heat  ex- 
pands the  CO2,  changes  the  alcohol  to  vapor  and  the 
water  to  steam.  All  these  by  their  expansive  force 
rapidly  increase  the  size  of  the  loaf.  When  the 
whole  loaf  has  been  heated  to  about  350°  F.,  the  fer- 
mentation is  checked,  and  if  the  temperature  of  the 
oven  is  right,  the  cells  of  the  bread  will  have  suffi- 
cient strength  to  retain  their  form  after  the  gas  and 
vapors  have  escaped.  If  the  heat  is  not  sufficient, 
or  if  there  is  too  much  water  in  the  dough,  the  CO2 
escapes,  and  the  cells,  not  having  hardened  suffi- 
ciently, collapse,  and  the  bread  is  "slack-baked." 
If  the  oven  is  too  hot,  a  crust  forms  over  the  surface 
of  the  loaf,  which  prevents  the  escape  of  the  CO2, 
so  it  accumulates  at  the  centre,  making  the  bread 
hollow.  A  part  of  the  starch  in  the  crust  is  con- 
verted by  the  heat  into  gum  (dextrine),  and  if  it  be 
burnt,  this  is  disorganized,  the  volatile  gases  driven 
off,  and  the  carbon  left.  A  shiny  coat  is  given  to  the 
loaf  ("rusk")  by  moistening  the  crust  after  the  bread 
is  baked,  thus  dissolving  some  of  the  gum,  which 
quickly  dries  on  returning  it  to  the  oven. 

Milk-emptyings  is  sometimes  used  in  making  bread. 
In  this  case,  the  mixture  of  flour  and  milk,  kept  at 
a  temperature  of  90°,  develops  yeast,  which  produces 
fermentation.  If  the  heat  is  over  90°,  the  yeast 
plant  is  killed ;  if  lower,  it  is  not  formed.  In  the 


214  ELEMENTARY  CHEMISTRY. 

latter  case,  the  milk  is  merely  turned  to  lactic  acid. 
Oftentimes,  too,  the  side  of  the  dish,  near  the  fire, 
may  be  warm  enough  to  produce  yeast  and  to  gen- 
erate CO2  and  alcohol,  while  on  the  opposite  side 
lactic  acid  is  being  formed.  A  uniform  temperature 
is  necessary,  and  this  can  best  be  obtained  by  pla- 
cing the  dish  of  emptyings  in  a  kettle  of  warm  water 
on  the  stove  hearth,  where  the  temperature  can  be 
kept  very  near  the  requisite  90°. 

STALE  BREAD. — New  bread  consists  of  nearly  one 
half  water.  In  stale  bread  this  disappears.  It  has, 
however,  only  combined  with  the  solid  portions 
chemically,  and  may  be  brought  to  view  by  heating 
the  loaf  in  a  close  tin  vessel. 

AERATED  BREAD  is  not  "  raised"  by  fermentation, 
but  by  means  of  CO2,  which  is  forced  into  it  by  great 
pressure. 

SOUR  BREAD  is  caused  by  the  first  stage  of  the 
fermentation  not  being  stopped  soon  enough,  and 
the  second  stage  commencing,  in  which  acetic  acid 
is  formed.  This  may  be  neutralized  by  an  alkali,  as 
saleratus  (KO.2CO2),  or  soda  (NaO.2CO2). 

PAN-CAKES  are  raised  by  the  addition  of  some  fer- 
ment, as  yeast,  but  the  second,  or  acetous  stage,  is 
always  reached.  The  "  batter"  now  tastes  sour,  #nd  is 
sweetened  by  saleratus  or  soda.  The  acetic  acid 
combines  with  the  KO  (if  saleratus  is  used),  forming 
acetate  of  potassa,  a  neutral  salt  which  remains,  and 
the  CO2  bubbles  up  through  the  batter,  making  it 
"light." 


DOMESTIC   CHEMISTRY.  215 

EAISING  BISCUIT. — In  raising  biscuit  or  cake,  soda 
and  cream  of  tartar  are  most  commonly  used.  The 
latter  is  a  bitartrate  of  potassa,  and  the  reaction  is 
as  follows : 


Na0.2CO2  +  K0.2T 


Cream  of  tartar  is  now  often  adulterated  with  plaster, 
lime,  chalk,  or  flour.  By  dissolving  in  water  these 
can  be  detected,  as  they  form  an  insoluble  precipi- 
tate ;  but  in  milk,  as  commonly  used  in  cooking, 
they  are  not  noticed.  Common  "baking-powders" 
contain  simply  cream  of  tartar  and  soda.  Professor 
Hosford's  powders  are  scientific.  They  contain 
phosphate  of  lime  and  soda.  The  reaction  is  the 
same  as  that  just  described,  while  phosphates  of  lime 
and  soda  are  formed,  both  of  which  are  materials  for 
bone-making.  Soda  and  HC1  are  also  used  in  bak- 
ing. By  heat  both  constituents  are  resolved  into 
HO,  CO2,  and  NaCl.  The  HO  and  CO2  raise  the 
bread,  while  the  common  salt  seasons  it.  There  is  a 
difficulty  in  procuring  pure  acid  and  in  mixing  the 
ingredients  in  their  combining  proportions. 

Bread  Dietetics. — It  is  doubtful  whether  ordinary 
yeast-powders  or  cream  of  tartar  and  soda  make  as 
healthy  food  as  the  regular  process  of  fermentation. 
There  is  frequently  a  portion  of  the  powders  left  un- 


216  ELEMENTARY  CHEMISTRY. 

combined,  and  always  a  salt  formed  which  may  in- 
jure the  gastric  juice.  Sometimes,  indeed,  we  find 
biscuit  and  cake  yellow,  and  even  spotted  with  bits 
of  saleratus  ;  yet  such  food  must  be  "  eaten  to  save 
it."  A  most  wretched  mistake  !  Better  throw  away 
pans  of  cake  and  biscuit  than  torment  Nature  with 
such  nauseous,  poisonous  preparations.  Sal-volatile 
or  carbonate  of  ammonia  is  often  used  by  bakers  for 
raising  cake.  This  should  volatilize  into  two  gases, 
NH3  and  CO2,  on  the  application  of  heat,  but  in  prac- 
tice a  portion  is  left  commonly  hidden  in  the  cake 
to  work  injury  to  the  inoffensive  stomach. 

TOASTING  BREAD. — By  toasting  bread  it  becomes 
much  more  digestible,  as  the  starch  is  converted 
largely  into  gum,  which  is  soluble.  The  charcoal 
which  may  be  formed  when  the  heat  has  disorgan- 
ized the  bread  and  driven  off  the  water,  also  acts 
favorably  on  the  stomach  by  absorbing  in  its  pores 
noxious  gases,  as  in  "  crust  coffee." 

COOKING  POTATOES. — A  raw  potato  is  indigestible, 
but  by  cooking,  the  starch  granules  absorb  the  water 
of  the  potatoe,  burst,  and  make  it  "  mealy."  If  the 
potatoe  contains  more  HO  than  the  starch  can  im- 
bibe, it  is  called  "  watery." 

COOKING  MEAT. — All  fried  food  is  unhealthy,  since 
the  fat  is  partly  disorganized  by  the  heat,  and  there- 
fore becomes  rancid  on  the  stomach.  Broiling  and 
boiling  are  the  most  preferable  methods  of  cooking. 
In  the  former  no  butter  should  be  used,  and  the  juices 
should  not  be  pressed  out  of  the  meat,  but  the  heat 


DOMESTIC   CHEMISTRY.  217 

should  be  intense  enough  to  sear  over  the  outside 
instantly,  and  prevent  "  dripping"  on  the  coals.  In 
the  latter,  the  water  should  boil  when  the  meat  is 
put  in,  so  as  to  coagulate  the  albumen  upon  the  out- 
side, close  the  pores,  and  thus  keep  the  juices  of  the 
meat  within,  otherwise  it  will  become  tough,  and 
much  also  of  its  value  will  be  lost.  In  making  soup, 
on  the  contrary,  as  the  object  is  to  extract  the  juices 
of  the  meat,  cold  water  should  be  used.  It  should 
be  heated  slowly,  and  boiled  only  for  a  few  moments 
just  before  it  is  taken  off  from  the  fire.  Long  con- 
tinued boiling  would  coagulate  that  which  should 
remain  dissolved  in  the  soup.  In  baking,  the  oven 
should  be  very  hot  at  first,  to  prevent  the  meat  from 
becoming  dry  and  unsavory.  When  meat  burns, 
the  heat  has  become  so  intense  as  to  disorganize  the 
flesh,  driving  off  the  HO  and  volatile  gases,  and 
leaving  the  C. 

WATER  IN  COOKING. — The  solvent  power  of  soft 
water  is  greater  than  that  of  hard  water.  For  this 
reason,  in  making  soup,  tea,  etc.,  the  former  should 
be  used ;  in  boiling  meats  and  cooking  vegetables, 
where  the  object  is  not  to  extract  the  flavor  or  juices, 
the  latter  is  preferable.  Sometimes  in  cooking  very 
delicate  vegetables,  as  onions,  the  hardness  of  the 
water  must  be  increased  by  adding  salt  to  prevent 
their  sweetness  from  dissolving.  Salt  is  not  put  into 
vegetables,  when  boiling  them,  so  much  to  flavor  them 
as  to  preserve  their  aroma,  which,  if  lost,  no  subse- 
quent salting  will  restore.  Peas  and  beans  will  not 

10 


218  ELEMENTARY  CHEMISTRY. 

cook  soft  in  hard  water,  because  the  mineral  matter 
hardens  the  casein  they  contain.  A  soup  cannot  be 
made  of  salt  meat. 

QUANTITY  or  FOOD  EEQUIRED. — To  repair  the  con- 
stant waste  of  the  body,  we  each  require  about  800 
Ibs.  of  food,  1500  of  water,  and  800  of  oxygen  per 
annum.  A  ton  and  a  half  of  material  is  thus  needed 
each  year  to  preserve  intact  our  corporeal  system. 
We  take  in  each  day  about  10  Ibs.  of  matter,  yet 
may  not  gain  an  ounce  in  weight.  This  large 
amount  passing  through  the  mould  of  our  body  is 
all  burned — i.  e.,  combines  with  O.  This  must  be  a 
renewed  proof  of  the  statement  made  under  the  sub- 
ject of  oxygen,  that  the  vital  principle  does  not  pre- 
vent decay,  but  only  regulates  it,  and  that  the  moment 
we  begin  to  live  we  begin  to  die. 

THE  EFFECT  OF  FOOD. — There  is  an  ancient  saying, 
"  Tell  me  what  a  man  eats  and  I  will  tell  you  what 
he  is."  A  man's  nvnd  sympathizes  so  intimately 
with  his  body,  that  through  the  body  the  soul  itself 
may  be  gradually  animalized  by  gross  food.  The 
coarse  feeder  and  the  fine  feeder  become  as  different 
in  their  feelings  as  they  are  in  their  food.  Aninml 
food  inflames ;  vegetable,  calms.  The  passionate  re- 
quire a  vegetable  diet,  while  the  phlegmatic  may 
stimulate  with  flesh.  Compare,  for  example,  the 
dreamy  vegetarian  H:'ndoo  with  the  fierce,  meat- 
eating  Indian. 

THE  DIVISIO  so7  R)  D. — All  food  is  divided  into 
two  .  general  classes—" ;  ext-malwng"  and  "  muscle-' 


DOMESTIC   CHEMISTRY.  '219 

making"  or  respiratory  and  nutritive.  The  former 
comprises  all  such  articles  as  are  burned  in  our  cor- 
poreal stove,  as  wood  is  in  a  furnace,  mainly  to  pro- 
duce heat.  Example  :  Alcohol,  starch,  sugar,  gum, 
fat,  butter,  etc.  The  latter  includes  such  as  are 
transformed  into  flesh  and  bone,  and  thus  build  up 
our  bodies  in  some  manner.  Example  :  Lean  meat, 
bread,  milk,  etc.  Each  of  these  contains  a  mixture 
of  both  to  a  certain  extent,  but  is  mainly  either 
respiratory  or  nutritive.  Example  :  Fat  is  deposit- 
ed in  cells  which  are  probably  nutritive,  and,  on  the 
other  hand,  bread  contains  starch,  which  is  respira- 
tory. 

NUTRITIVE  YALUE  OF  FOOD  OF  DIFFERENT  KINDS. — 
The  following  table,  from  Liebig,  illustrates  this  sub- 
ject : 

Nutritive.    Respiratory. 

Cows'  milk 1  3. 

Beans 1  2.2 

Peas 1  2.3 

Fat  mutton 1  2.7 

Fat  pork 1  3. 

Beef 1  1.7 

Veal 1  .1 

Wheat  flour 1  4.6 

Oatmeal 1  5. 

Rye  flour 1  5.7 

Barley 1  5.7 

Potatoes  (white) 1  8.6 

Potatoes  (blue) 1  11.5 

Rice 1  12.3 

Buckwheat 1  13. 

Sugar,  alcohol,  oil,  etc.,  are  heating  and  fattening. 
.They  make  no.  muscle,  no  brain,  no  nervous  tissue. 


220  ELEMENTARY   CHEMISTRY. 

The  bran  of  wheat  contains  largely  the  mineral  mat- 
ter we  need  for  our  bones  and  teeth  and  the  nutri- 
tive food  for  our  muscles.  The  whiteness  of  fine 
flour  ("  bolted"  from  its  bran)  is  given  to  it  by  its 
starch.  Our  bones  and  muscles  call  loudly  for  the 
flour  unbolted,  as  Nature  designed  it  to  meet  our 
wants.  Pork  is  only  half  as  nutritious  as  beef,  and 
is  hence  worth  for  work  only  half  price.  Besides, 
the  hog  is  a  filthy  animal,  a  gross  feeder,  and  sub- 
ject to  so  many  cutaneous  diseases,  that  he  will 
even  stop  eating  for  the  luxury  of  being  scratched. 
Its  flesh  was  doubtless  never  designed  for  Yankee 
any  more  than  for  Jew.  The  workman  gains  strength, 
not  from  the  pork  he  eats,  but  the  turnips,  cabbage 
(in  its  composition  so  near  to  beefsteak),  milk,  eggs, 
and  other  plastic  or  nutritive  food. 

CLIMATE  PRESCRIBES  THE  KIND  OF  FOOD. — The  Es- 
quimaux Indian,  with  a  climate  many  degrees  be- 
low zero,  needs  much  fire  in  his  stove ;  so  he  lives 
mainly  qn  fats.  Tallow  candles  constitute  his  sweet- 
meats— twelve  pounds  making  a  luxurious  dessert. 
Dr.  Kane  tells  us  that  they  would  steal  the  half-burned 
wicks  out  of  his  candlesticks  and  draw  them  slowly 
between  their  teeth,  to  secure  the  adhering  grease. 
Indeed,  their  idea  of  heaven  is  said  to  be  that  there 
the  righteous  will  live  in  ice-huts,  and  feast  forever  on 
blubber.  An  American  living  in  the  Arctic  regions 
soon  acquires  much  of  an  Esquimaux's  love  for  fats 
and  oils.  Nature  has  providentially  provided  there 
that  kind  of  food,  and  not  much  else.  Turn  now  to 


DOMESTIC   CHEMISTRY.  221 

the  tropics,  where  the  temperature  is  so  high  that  all 
one's  attention  is  taken  up  in  keeping  cool,  and  we 
find  an  entire  change  in  the  diet  of  the  inhabitants. 
The  natives  confine  themselves  almost  entirely  to 
vegetables,  and  with  this  watery  fuel  reduce  the  heat 
of  their  bodies  to  the  lowest  point. 

A  MIXED  DIET  REQUIRED. — Nature  seems  to  pre- 
scribe a  mixed  diet,  to  supply  both  wants  of  the 
system,  and  has,  to  some  extent,  mixed  them  her- 
self in  the  various  kinds  of  food.  The  Frenchman 
eats  oil  on  his  salad,  the  Yankee  bakes  beans  with 
his  pork,  the  Italian  begs  a  bit  of  cheese  for  his 
maccaroni,  the  Irishman  drinks  buttermilk  with  his 
potatoes,  the  Hindoo  pours  rancid  butter  on  his 
rice,  while  the  Chinaman  seasons  his  with  pea 
cheese.  No  amount  of  starch  or  fat  would  support 
life.  A  man  would  starve  on  sugar  or  butter  alone. 
The  nitrogenous  or  nutritive  element  must  be  added. 
The  season  also  regulates  our  diet.  In  the  winter 
the  highly  respiratory  buckwheat,  with  butter  and 
syrup,  is  perfectly  palatable,  while  in  summer  acid 
drinks,  watery  vegetables,  and  a  simple  unstimula- 
ting  diet  is  equally  enjoyed. 


222  ELEMENTARY  CHEMISTRY. 


CONCLUSION. 

CHEMISTRY  OF  THE  SUNBEAM. — All  those  various 
plant  products  of  which  we  have  spoken  in  Organic 
Chemistry,  when  burned,  either  in  the  body  as  food 
or  in  the  air  as  fuel,  give  off  heat.  This  was  garnered 
in  the  plant  while  growing,  and  came  from  that 
great  source  of  heat — the  sun.  Thus  all  vegetation 
contains  the  latent  heat  of  the  sunbeam,  ready  to  be 
set  free  upon  its  own  oxydation.  The  coal  even,  de- 
rived as  it  is  from  ancient  vegetation,  hidden 
away  in  the  earth,  is  thus  a  mine  of  reserved  force. 
Those  black  diamonds  we  use  as  fuel  become,  in  the 
eye  of  science,  crystallized  sunbeams,  fagots  of  force, 
ready  to  impart  to  us  at  any  moment  the  heat  of 
some  old  carboniferous  day.  As  we  warm  ourselves 
by  our  fires,  or  sit  and  read  by  our  oil  and  gas  lights, 
how  strange  the  thought  that  their  light  and  heat 
streamed  down  upon  the  earth  ages  ago,  were  ab- 
sorbed by  those  grotesque  leaves  of  the  old  coal 
forests,  and  kept  safely  stored  away  by  a  Divine 
care,  in  order  to  provide  for  our  comfort !  To  carry 
the  idea  still  further,  we  see  that  the  present  warmth 
of  our  bodies  all  comes  from  the  same  source — the 
sun.  It  mostly  fell  in  the  sunbeams  of  last  summer 
upon  our  gardens  and  fields,  was  preserved  in  the 


CONCLUSION.  223 

potatoes,  cabbage,  corn,  etc.,  we  have  eaten,  as  fuel, 
and  to-day  reappears  as  heat  and  motion. 

CHANGES  OF  MATTER. — Chemical  changes  are  taking 
place  wherever  we  look — on  land  or  sea.  The  hard 
granite  crumbles  and  moulders  into  dust.  The  stout 
oak  takes  in  the  air  and  solidifies  it ;  takes  up  the 
earth  and  vitalizes  it ;  changes  all  into  its  own  struc- 
ture, and  proudly  stands  monarch  of  the  forest. 
But  in  time  its  leaves  turn  yellow  and  sere,  its 
branches  crumble,  itself  totters,  falls,  and  disappears. 
Our  own  bodies  seem  to  us  comparatively  stable, 
but,  with  the  rock  and  the  oak,  they  too  pass  away. 
All  Nature  is  a  torrent  of  ceaseless  change.  We  are 
but  parts  of  a  grand  system,  and  the  elements  we 
use  are  not  our  own.  The  water  we  drink  and  the 
food  we  eat  to-day  may  have  been  used  a  thousand 
times  before,  and  that  by  the  vilest  beggar  or  the 
dirtiest  earth-worm.  In  Nature  all  is  common,  and 
no  use  is  base.  She  keeps  no  selected  elements 
done  up  in  gilt  papers  for  sensitive  people.  Those 
particles  of  matter  we  so  fondly  call  our  own,  and 
decorate  so  carefully,  a  few  months  hence  may  have 
dragged  boats  on  the  canal,  or  waved  in  the  meadow 
as  grass  or  corn.  From  us  they  will  pass  on  their 
ceaseless  round  to  develop  other  forms  of  vegeta- 
tion and  life,  whereby  the  same  atom  may  freeze  on 
arctic  snows,  bleach  on  torrid  plains,  be  beauty  in 
the  poet's  brain,  strength  in  the  blacksmith's  arm, 
or  beef  on  the  butcher's  block.  Hamlet  must  have 
been  somewhat  more  of  a  chemist  than  a  madman 


224  ELEMENTARY  CHEMISTEY. 

when  lie  gravely  assured  the  king  that  "  man  may 
fish  with  the  worm  that  hath  eat  of  a  king,  and  eat 
of  the  fish  that  hath  fed  of  the  worm."  Life  and 
death  are  thus,  throughout  Nature,  commensurate 
with  and  companions  of  each  other.  Oxygen  is  the 
destroyer.  It  tears  down  every  living  structure,  and 
would  bring  all  things  to  rest  in  ashes.  The  sun- 
beam is  its  antagonist.  It  rebuilds  and  reinvigor- 
ates. 

THE  SUN  THE  SOURCE  OF  POWER. — The  sun  warms, 
enlivens,  and  animates  the  earth.  In  the  laboratory 
of  the  leaf  it  works  the  most  wonderful  chemical 
changes.  We  see  its  handiwork  in  the  building  of 
the  forest,  the  carpeting  of  the  meadow,  and  the 
tinting  of  the  rose.  On  the  ladder  of  the  sunbeam 
water  climbs  to  the  sky,  and  falls  again  as  rain. 
The  very  thunder  of  Niagara  is  but  the  sudden  un- 
bending of  the  spring  that  was  first  coiled  by  the 
sun  in  the  evaporation  from  the  ocean.  Up  to  the 
sun,  then,  we  trace  all  the  hidden  manifestations  of 
power.  Yet  the  force  that  produces  such  intricate 
and  wide-extended  changes  is  but  one  twenty-three 
hundred  millionth  part  of  the  tide  that  flows  in 
every  direction  from  this  great  central  orb.  But 
what  is  our  sun  itself  save  a  twinkling  star  beside 
great  suns  like  Sirius,  and  Eegulus,  and  Procyon, 
whose  brilliancy  in  the  far-off  regions  of  space 
drowns  our  little  sun  as  the  dazzling  light  of  day 
does  the  smouldering  blaze  of  some  wandering 
hunter? 


CONCLUSION.  225 

Thus  have  we  traced  some  of  the  wonderful  pro- 
cesses by  which  this  world  has  been  arranged  to 
supply  the  varied  wants  of  man.  Wherever  we  have 
turned,  we  have  found  proofs  of  a  Divine  care  plan- 
ning, conforming,  and  directing  to  one  universal  end, 
while  from  the  commonest  things  and  by  the  simplest 
means  the  grandest  results  have  been  attained.  Thus 
does  Nature  attest  the  sublime  truth  of  Revelation, 
that  in  all,  and  through  all,  and  over  all,  the  Lord 
God  omnipotent  reigneth. 

10* 


APPENDIX. 


PEOBLEMS. 

MATHEMATICS  OF  CHEMISTRY. — In  solving  the  prob- 
lems given  on  the  17th  page,  some  may  prefer  to  use 
proportion.  The  following  will  suggest  the  method : 


The  equivalent  tf  the  given  constituent  :  equivalent  of  the  compound  :  :  weight  of  tht> 
constituent  :  weight  of  the  compound. 


Problem  1.  How  many  Ibs,  of  HO  are  there  in  a 
cwt.  ofS03.2HO? 

Solution — 

2HO  =  18  =  equivalent  of  the  given  constituent. 
S03 .  2HO  =  58  =  equivalent  of  the  compound. 

x  =  weight  of  the  constituent. 
100  Ibs.  =  weight  of  the  compound. 
18  :  58  : :  x  :  100  Ibs. 

x  =  31^  Ibs. 

Prob.  2.  How  much  sodium  is  there  in  20  gr.  of 

sal-soda  (NaO,CO?)? 


228  ELEMENTARY  CHEMISTBY. 

Solution  — 

Na  =  23  =  equivalent  of  the  given  constituent. 
NaO  =  31  =  equivalent  of  the  compound. 

x  =  weight  of  the  constituent. 
20  gr.  =  weight  of  the  compound. 
'      23  :  31  ::  x  :  20  gr. 


Prob.  3.  How  much  carbonate  of  lime  can  be 
formed  from  one  drachm  of  C? 

Solution  — 

C  =  6  =  equivalent  of  the  given  constituent. 
CaO.CO2  =  50  =  "          "  "      compound. 

1  dr.  =  weight  of  the  given  constituent. 
x  —  weight  of  the  compound. 
6  :  50  :  :  1  dr.  :  x. 
x  =  8|  drachms. 

Prob.  4.  How  much  C02  would  be  required  to 
neutralize  2  Ibs.  of  potash  ? 

Solution.  —  First  we  find  how  much  KO.CO2  two 
Ibs.  of  KO  will  make,  and  then  how  much  C02  will  be 
contained  in  that  amount  of  the  salt. 

(1.)     KO  =  47  =  equivalent  of  the  constituent. 
KO  .  CO2  =  69  =  equivalent  of  the  compound. 
2  Ibs.  =  weight  of  the  constituent. 
x  =  weight  of  the  compound. 
47  :  69  ::  2  Ibs.  :  x  =  Sftlbs.  =  weight  of  KO.CO,. 


APPENDIX.  229 

(2.)    CO2  =  22  =  equivalent  of  the  constituent. 
KO.C02*  =  69  =  equivalent  of  the  compound. 

x  =  weight  of  the  constituent. 
2£4  =  weight  of  the  compound. 

22  :  69  ::  x  :  2ff-lbs. 

The  remaining  problems  can  be  used  throughout 
the  term  at  the  discretion  of  the  teacher,  whenever 
the  appropriate  subject  is  under  consideration  in 
the  class. 

Prob.  5.  What  weight  of  0  is  contained  in  60  gr. 
ofKO.C105? 

Prob.  6.  How  much  KC1  will  be  formed  in  prepar- 
ing 80  gr.  of  O  ? 

Prob.  7.  How  much  H  can  be  made  from  10  Ibs. 
of  Zn? 

Prob.  8.  How  much  H  can  be  made  from  50  Ibs. 
of  water? 

Prob.  9.  How  much  saltpetre  will  be  required  to 
make  18  Ibs.  of  aquafortis  ? 

Prob.  10.  How  much  oil  of  vitriol  will  be  required 
4o  decompose  6  Ibs.  of  saltpetre  ? 

Prob.  11.  How  much  HO  will  be  decomposed  by 
one  drachm  of  K,  and  how  much  KO  will  be  formed  ? 

Prob.  12.  What  weight  of  nitrous  oxyd  will  be 
formed  from  the  decomposition  of  6  oz.  of  nitrate 
of  ammonia? 

Prob.  13.  How  much  sal-ammoniac  would  be  re- 
quired to  make  2  Ibs.  of  NH3? 

*  Some  late  authorities  give  the  equivalent  of  K  as  39.2,  which 
would  alight! v  change  tlii?  result. 


230  ELEMENTARY   CHEMISTRY. 

Prob.  14.  How  much  CO2  will  be  formed  in  the 
combustion  of  30  gr.  of  CO  ? 

Prob.  15.  What  weight  of  carbonate  of  soda  would 
be  required  to  evolve  12  Ibs.  of  CO2  ? 

Prob.  16.  What  weight  of  bicarbonate  of  soda 
(NaO.2CO2,  "soda")  would  evolve  12 Ibs.  of  CO2? 

Prob.  17.  What  weight  of  C  is  there  in  a  ton  of 
CO2? 

Prob.  18.  How  much  O  is  consumed  in  burning  a 
ton  of  C? 

Prob.  19.  In  burning  a  charge  of  10  Ibs.  of  gun- 
powder, find  the  weight  of  the  several  products 
formed. 

Prob.  20.  What  weight  of  common  salt  would  be 
required  to  form  25  Ibs.  of  muriatic  acid  (HC1)  ? 

Prob.  21.  HC1  of  a  specific  gravity  of  1.2  contains 
about  40  per  cent,  of  the  acid.  This  is  very  strong 
commercial  acid.  What  weight  of  this  acid  could 
be  formed  by  the  HC1  acid  gas  produced  in  the  re- 
action named  in  the  preceding  problem  ? 

Prob.  22.  What  weight  of  hydriodic  acid  (HI)  is 
formed  from  a  drachm  of  iodine  ? 

Prob.  23.  What  weight  of  Glauber  salts  can  be 
formed  from  100  Ibs.  of  oil  of  vitriol  ? 

Prob.  24.  What  weight  of  S  is  there  in  10  gr.  of 
sulphide  of  hydrogen? 

Prob.  25.  How  much  O  is  required  to  change  a  Ib. 
of  SO2toS03? 

Prob.  26.  How  much  phosphorus  in  40  Ibs.  of 
phosphate  of  lime?  .  ...„.- 


APPENDIX.  231 

Prob.  27.  How  much  P  in  40  Ibs.  of  the  super- 
phosphate of  lime? 

Prob.  28.  How  much  phosphate  of  lime  will  an 
oz.  of  P  make  ? 

Prob.  29.  How  many  Ibs.  of  HO  in  186  Ibs.  of 
S03.3HO? 

Prob.  30.  How  much  CO2  is  formed  in  the  com- 
bustion of  one  ton  of  C  ? 

Prob.  31.  What  weight  of  S  is  there  in  a  ton  of 
iron  pyrites  ? 

Prob.  32.  What  weight  of  copperas  could  be  made 
from  500  Ibs.  of  iron  pyrites  ? 

Prob.  33.  What  weight  of  H  is  there  in  a  pound  of 
heavy  carburetted  hydrogen  ? 

Prob.  34.  How  much  O  would  be  required  to  oxyd- 
ize  the  metallic  copper  which  could  be  reduced  from 
its  oxyd  by  passing  over  it,  when  white-hot,  20  gr. 
of  Hgas? 

Prob.  35.  How  much  O  would  be  required  to 
oxydize  the  metallic  iron  which  could  be  reduced  in 
the  same  manner  by  10  gr.  of  H  gas  ? 

Prob.  36.  What  weight  of  N  is  there  in  10  Ibs.  of 
NH3.HO? 

Prob.  37.  How  much  KO .  C1O5  would  be  required 
to  evolve  sufficient  O  to  burn  the  H  produced  by  the 
decomposition  of  2  Ibs.  of  HO  ? 

Prob.  38.  How  much  H  must  be  burned  to  pro- 
duce a  ton  of  water  ? 

Prob.  39.  How  much  S  is  there  in  a  Ib.  of  S02  ? 


232  ELEMENTARY  CHEMISTRY. 


THE  ALKALIES. 

Problem  40.  As  soda  is  used  so  extensively  in  the 
arts,  it  is  of  great  importance  to  all  consumers  of 
soap,  glass,  etc.,  that  it  should  be  manufactured  as 
cheaply  as  possible.  Leblanc's  process  of  making 
it  from  common  salt  is  now  universally  adopted. 
The  operation  comprises  two  stages :  (1)  Changing 
common  salt  into  sulphate  of  soda ;  and  (2),  the 
changing  of  this  sulphate  of  soda  into  carbonate  of 
soda. 

The  first  operation  is  performed  in  large  cast-iron 
pans,  about  12  inches  deep  at  the  centre,  and  9  feet 
diameter.  A  charge  of  500  Ibs.  of  salt  is  thrown 
into  one  of  t,hese  pans  with  about  an  equal  weight 
of  SO3,  and  heated.  The  sulphate  of  soda  is  formed 
with  an  evolution  of  HC1  fumes.  These  fumes  are 
conducted  into  the  bottom  of  a  vertical  flue,  filled 
with  pieces  of  coke,  wet  with  constantly  dripping 
water.  This  HO  absorbs  the  gas,  and  forms  a  very 
weak  muriatic  add,  in  immense  quantities. 

The  second  stage  consists  in  grinding  the  Glauber 
salts  (sulphate  of  soda)  with  an  equal  weight  of 
chalk  (CaO. C02),  and  half  its  weight  of  coal.  This 
mixture  is  heated  and  stirred  until  well  melted,  when 
it  is  raked  out  to  cool.  This  mass  is  called  "  black 
ash"  The  chemical  change  that  has  taken  place  is 
very  simple;  the  charcoal  deoxydized  the  salts, 
changing  the  sulphate  of  soda  into  the  sulphuret  of 
sodium.  The  sulphuret  of  sodium  then  reacted  with 


APPENDIX.  233 

the  carbonate  of  lime  forming  the  sulphuret  of  cal- 
cium and  the  carbonate  of  soda,  as  follows : 

NaS  +  CaO.CO2  =  CaS  +  NaO.CO2. 

The  carbonate  of  soda  alone  being  soluble  in  HO, 
is  dissolved  out  of  the  black  ash,  and  then  crystal- 
lized, producing  the  soda-ash  of  commerce. 

The  muriatic  acid,  which  is  an  incidental  product 
of  the  first  stage,  is  used  in  making  chloride  of  lime, 
so  extensirely  employed  in  bleaching.  The  sulphuret 
of  sodium  has  always  been  a  waste  product ;  but  at 
the  late  exposition  at  Paris  (1867),  blocks  of  sulphur, 
of  tons  weight  each,  were  exhibited,  which  had  been 
extracted  from  it  by  a  process  not  yet  divulged.  It 
is  said  that  200,000  tons  of  common  salt  are  annually 
used  in  the  alkali  manufactories  of  England. 

Find  how  much  "soda"  is  formed  from  500 Ibs. 
of  salt. 

Prob.  41.  Find  the  amount  of  Glauber  salts  pro- 
duced in  the  first  step,  with  the  charge  just  named. 

Prob.  42.  Find  the  amount  of  HC1  produced. 

Prob.  43.  Find  how  much  sulphuret  of  sodium  is 
formed  in  the  second  step. 

Prob.  44.  Find  how  much  sulphuret  of  calcium  is 
made. 

Prob.  45.  Find  how  much  sulphur  could  be  saved 
(if  none  were  lost)  from  the  CaS. 

Prob.  46.  How  many  Ibs.  of  HC1  would  be  required 
to  neutralize  sufficient  carbonate  of  ammonia  to 
form  a  30  Ib.  cake  of  sal-ammoniac  (NH4 .  Cl)  ? 


234  ELEMENTARY  CHEMISTRY. 

Prob.  47.  How  much  S  is  there  in  a  ton  of  plaster 
(gypsum)? 

Prob.  48.  How  much  aluminum  is  there  in  a  ton 
of  clay? 

Prob.  49.  How  much  K  is  there  in  10  Ibs.  of  alum? 

Prob.  50.  How  much  white-lead  (PbO .  CO2)  could 
be  made  from  a  Ib.  of  litharge  ? 

Prob.  51.  How  many  Ibs.  of  C  would  be  required 
to  reduce  40  tons  of  brown  Hematite  (2Fe2O3. 3HO)  ? 

Prob.  52.  In  60  Ibs.  of  heavy  spar  (sulphate  of 
baryta)  how  much  S  is  there  ? 

Prob.  53.  How  much  alum  can  be  made  from  1  cwt. 
of  potash? 

THE  METALLOIDS. 

(Page  18.)  OXYGEN. — In  making  this  gas,  a  cop- 
per flask  and  rubber  tubing  should  be  used,  as  it  is 
by  far  the  cheapest  apparatus.  Great  care  should  be 


a  Copper  retort. 

b  A  copper  tube  leading  from  it. 

c  Tube  of  india-rubber  to  convey  the  gas  to  a  gas-bag, 

gasometer,  or  pneumatic  trough. 
d  GHS-bag. 
«  Spirit-lamp. 


APPENDIX.  235 

taken  in  pulverizing  the  KO,  C1O5,  as  a  pressure  of 
more  than  10  Ibs.  is  liable  to  produce  an  explosion. 
For  the  experiments  with  the  watch-spring,  phos- 
phorus, etc.,  common  "specie  jars"  will  be  found 
very  convenient,  or,  in  necessity,  any  wide-mouthed 
bottles  which  can  be  obtained  of  a  druggist. — The 
author  will  be  pleased  to  correspond  with  any  teacher 
who  may  be  desirous  of  information  concerning  the 
apparatus  which  is  needed,  and  the  simplest  method 
of  performing  the  various  experiments.  Priced  lists 
of  apparatus,  chemicals,  etc.,  can  be  obtained,  on 
application,  from  Messrs.  J.  Nellegar  &  Co.  (late 
Messrs.  Dexter  &  Nellegar),  Albany,  N.  Y. 

(Page  34.)  NITROUS  OXYD. — A  special  apparatus 
is  necessary  both  for  preparing  and  inhaling  this 
gas  safely.  This  consists  of  a  glass  retort — as  shown 
in  the  cut — a  wash-bottle,  and  in  addition  a  gas-bag 
of  from  20  to  50  galls,  capacity  for  storing  the  gas, 
and  a  smaller  bag  of  from  3  to  5  galls.,  with  a  wide, 
wooden  mouth-piece  for  inhalation.  It  is  well  to  pass 
the  gas  through  a  large  wash-bottle,  as  shown  in  the 
cut  on  page  41,  half  full  of  HO,  thence  by  a  rubber 
tube  directly  into  the  large  gas-bag.  Before  making 
the  gas,  pour  into  the  bag  a  couple  of  gallons  of 
HO :  by  standing  in  the  bag  over  this  the  gas  will 
be  purifi  d  in  a  few  hours.  When  about  to  admin- 
ister the  gas,  let  the  subject  grasp  his  nose  firmly 
between  his  thumb  and  forefinger:  then,  inserting 
the  wooden  mouth-piece,  be  careful  that  he  does  not 
inhale  any  of  the  external  air,  but  takes  full,  deep 


236 


ELEMENTARY  CHEMISTKY. 


breaths  in  and  out  of  the  gas-bag.  Watch  the  eye 
of  xthe  subject,  and  notice  the  influence  of  the  gas. 
Commonly,  the  best  effect  is  not  reached  until  he 
begins  to  surge  backward  and  forward. 

(Page  43.)  The  zinc  for  making  hydrogen  should 
be  granulated.  This  is  easily  effected  by  pouring 
the  melted  metal  slowly  from  the  ladle  into  a  basin 
of  HO.  A  common  junk-bottle,  fitted  with  a  cork 
and  a  glass  tube,  will  answer  for  the  evolution  of  the 
gas,  but  a  "  hydrogen  generator,"  as  sold  by  appa- 
ratus dealers,  is  much  more  satisfactory.  In  experi- 


Hydrogen  Generator. 

menting  with  H,  great  care  must  be  used  not  to 
ignite  the  jet  of  gas  until  all  the  common  air  has 
passed  out  of  the  flask ;  otherwise  a  severe  explosion 
will  ensue.  It  is  a  safe  precaution  to  test  the  gas 
by  passing  it  in  bubbles  up  through  HO,  and  igniting 
them  at  the  surface;  the  force  of  the  combustion 
will  indicate  if  there  be  any  danger.  It  must  not 
be  kept  for  any  great  length  of  time  in  bags,  as  the 
air  will  gradually  force  itself  in,  and  the  gas  will 


APPENDIX.  237 

partly  pass  out  by  the  law  of  diffusion,  thus  form- 
ing a  mixture  which  it  is  dangerous  to  ignite. 
The  adjoining  illustration  of  a  jet  of  burning  H  is 
a  representation  of  what  is  called  "  The 
Philosopher's  Lamp."  In  using  the 
"  mixed  gases,"  the  utmost  care  is  requi- 
site. The  gases  may  be  passed  into  a 
gas-bag,  made  of  a  common  bladder, 
furnished  with  a  stop-cock.  A  clay  to- 
bacco pipe  may  be  attached  to  it  by 
means  of  a  bit  of  rubber  tubing.  A 
plate  of  good  soapsuds  makes  the  outfit 
complete.  Blow  the  bubbles  with  the 
gases  in  the  bag,  either  in  the  air,  or  on 
the  tin  plate,  but  be  cautious  not  to 
ignite  them  until  the  stop-cock  is  turned, 
and  the  bag  withdrawn  from  the  dish.  Pure  H 
bubbles  may  be  blown  in  the  same  manner :  if  out 
of  doors,  they  will  float  off  to  a  great  distance.  H 
may  be  better  purified  for  inhaling,  by  passing  it 
through  a  solution  of  potash,  with  some  alcohol 
added  to  it.  The  action  of  platinum 
sponge  is  best  shown  by  the  instru- 
ment represented  in  the  cut.  It  was 
formerly  used  by  chemists  as  a  con- 
venient way  of  obtaining  a  light  in 
the  laboratory.  Friction  matches  have 
superseded  such  clumsy  inventions. 
The  experiments  with  the  compound 

blowpipe,  as  Shown  in  the  frontispiece,  Dobereiner'e  Lamp. 


238 


ELEMENTARY  CHEMISTRY. 


can  be  given  either  by  the  use  of  gasometers,  or,  in 
their  stead,  rubber  gas-bags  may  be  substituted  at  a 

much  lower  price.  The 
H  gun — which  is  simply  a 
tin  tube,  closed  at  one  end, 
and  provided  with  a  cork 
at  the  other,  having  a 
priming-hole  at  the  side — 
may  be  filled  over  the 
Philosopher's  Lamp  when 
not  ignited.  The  gas  is  al- 
low'ed  to  pass  in  until  the 
gun  is  about  a  fifth  full,  as 
nearly  as  one  can  guess. 

Some  teachers  will  pre- 
fer to  use  the  more  exact 
chemical  term  "  molecule," 
when  speaking  of  a  com- 
pound, to  the  word  "  atom,"  as  employed  in  the  text. 
Molecule  means  the  smallest  quantity  of  a  compound 
that  can  exist  by  itself.  Thus  the  exact  language 
of  such  would  be — "An  atom  of  H  and  one  of  O 
unite,  and  form  a  molecule  of  HO."  This  term  can 
be  substituted  very  easily  by  those  who  desire  it. 
The  author  has  not  employed  it,  lest  he  might  con- 
fuse some  beginners  by  an  unnecessary  scientific 
term. 

(Page  47.)  WATER  is  analyzed  by  the  action  of 
the  galvanic  current  in  the  manner  shown  in  the  fol- 
lowing cut.  We  analyze  it  when  we  put  upon  our  coal 


Gasometer. 


APPENDIX. 


fire  cinders  wet  with  HO. 
The  HO  adds  to  the  inten- 
sity of  the  fire,  and  "  makes 
it  burn  better,"  as  we  say. 

(Page  55.)  THE  DIAMOND. 
— Although  the  diamond  is 
simply  pure  carbon,  yet 
it  has  never  been  made  Analysis  of  water. 

by  any  chemical  process.  Minute  diamonds,  it  is 
said,  have  been  separated  from  carbon  compounds 
by  long-continued  voltaic  action,  but  they  were  in- 
visible except  by  a  microscope.  The  value  of  the 
diamond  varies  with  the  market ;  the  general  rule  is 
as  follows :  a  gem  ready  for  setting,  of  one  carat 
weight,  is  worth  $40  to  $60 ;  beyond  this  size,  its 
value  increases  according  to  the  square  of  its  weight. 
The  Kohinoor  (mountain  of  light)  weighs  103  carats, 
and  is  valued  at  $10,000,000. 

(Page  64.)  CARBONIC  ACID. — The  experiments 
with  this  gas  may  be  still  further  varied  by  having 
at  the  bottom  of  the  inclined  plane  shown  in  the 
cut  on  page  65,  a  light  model  of  a  water-wheel. 
The  invisible  gas  flowing  down-hill  will  turn  it  very 
freely,  especially  if  too  many  candles  are  not  burn- 
ing at  the  time. 

Ventilation  is  thought  by  many  to  be  perfectly  pro- 
vided for  if  there  be  a  ventilator  placed  at  the  top 
of  the  room,  presenting  one  small  opening  for  the 
egress  of  the  bad  air.  To  show  the  fallacy  of  this, 
we  need  only  perform  the  experiment  represented  in 


240  ELEMENTARY  CHEMISTKY. 

the  adjoining  cut.  The  bottle  is  fitted  with  a  tin 
cover,  through  which  a  tube  is  inserted.  The  jar 
represents  a  room  sealed  tightly  on  all  sides  against 


the  incoming  of  the  air,  and  with  only  one  opening 
for  ventilation.  Place  a  lighted  candle  at  the  bot- 
tom, and  it  will  soon  be  extinguished,  no  O  seeming 
to  come  in  to  feed  the  flame.  Place  now  in  the  tube 
a  slide,  composed  of  two  slips  of  tin  soldered  at 
right  angles  to  each  other,  thus  dividing  the  tube 
into  four  longitudinal  portions.  The  lighted  candle 
will  burn  freely,  and  a  bit  of  smoking  paper  held  at 
the  top  of  the  tube  will  reveal  a  current  passing 
downward  through  two  of  the  openings,  and  a  cur- 
rent passing  outward  through  the  opposite  ones. 
This  shows  very  clearly  the  effect  of  a  division  in  the 
opening  used  for  ventilation.  Of  course,  no  room 
can  be  made  as  nearly  air-tight  as  the  bottle,  since 
some  air  will  come  in  at  the  sides,  around  the  win- 


APPENDIX. 


241 


dows,  etc. ;  still,  this  experiment  illustrates  the  im- 
perfection of  the  ordinary  ventilator.  The  necessity 
of  some  means  of  changing  the  air  is  shown  by  the 
fact,  that  two  persons  sleeping  in  a  room  15  ft.  square 
will  vitiate  the  atmosphere  in  three  hours, 
and  so  rebreathe  it  twice  before  morning,  and 
then  wonder  why  they  wake  up  with  a  head- 
ache. 

(Page  73.)  CYANOGEN. — The  pupil  will  here 
distinguish  ferrocyanide  of  potassium  from 
the  ferricyanide.  The  latter  is  the  red  prus- 
siate  of  potash.  When  the  yellow  prussiate 
is  added  to  a  salt  of  the  sesquioxyd  of  iron, 
prussian  blue  is  formed.  This  is  employed 
in  water-colors  and  oil-paintings,  and  when 
dissolved  in  oxalic  acid,  constitutes  blue  ink. 

(Page  83.)  THE  LAW  OF  DIFFUSION  may  be  finely 
illustrated  by  the  experiment  shown  in  the 
cut.  The  upper  jar 
is  to  be  filled  with 
H,  and  the  lower 
one  with  CO2.  The 
result  will  be  that 
described  in  the 
text. 

fPageSG.)  CHLO- 
RINE.— In  the  arts, 
and  for  many  ex- 
periments, Cl  is 
made  by  simply 


a  1'neumatic  trough,  d  Bell  glass  receiver. 

b  Retort.  e  Shelf  in  pneumatic  trough. 

c  Lamp-stand.  /  Spirit-lamp. 

11 


242  ELEMENTARY  CHEMISTRY. 

heating,  in  a  glass  retort,  black  oxyd  of  manganese, 
with  muriatic  acid.     The  reaction  is  this  : 

MnO2  +  2HC1  =  MnCl  +  2HO  +  Cl. 

Indeed,  most  of  the  experiments  in  Cl  may  be  per- 
formed by  taking  a  deep  glass  jar,  and  placing  at  the 
bottom  some  chloride  of  lime.  By  pouring  upon  this 
a  little  dilute  SO3,  the  Cl  will  soon  fill  the  jar  and  dis- 
place the  air.  Phosphorus  will  in- 
flame spontaneously  in  CL  The  gas 
is  very  annoying,  and  the  room  must 
be  thoroughly  ventilated. 

In  preparing  Cl,  as  mentioned  in 
the  text,  take  four  parts  of  common 
salt  and  mix  it  thoroughly  with  three 
parts  of  black  oxyd  of  manganese; 
Phosphorus  in  ci.     put  this  mixture  in  the  retort,  and 
pour  upon  it  dilute  SO3.     The  gas  will  be  evolved 
abundantly.     The  reaction  is  as  follows  : 

MnO2  +  NaCl  +  2SO3 .  HO  =  MnO .  SO3 + NaO .  SO3. 
HO+C1. 

The  gas  should  be  collected  over  warm  water,  as  it 
is  largely  absorbed  by  cold  water.  By  passing  the 
gas  for  some  time  through  a  bottle  of  HO,  a  solution 
will  be  formed  which  will  perform  all  the  experiments 
in  bleaching  very  nicely.  To  illustrate  this,  pour 
some  of  the  chlorine-water  into  a  test-tube  of  HO 
blackened  with  a  few  drops  of  ink. 

(Page  88.)    BLEACHING  POWDER  is  considered  to 
be  a  mixture  of  the  chloride  of  calcium   and  the 


APPENDIX. 


243 


hypochlorite*  of  lime— thus,  CaCl  +  CaO .  CIO.  It  is 
produced  in  great  quantities  in  the  process  of  making 
sal-soda. 

(Page  93.)  BIBORATE  OF  SODA  (NaO.2BO3+10HO) 
is  used  in  soldering  and  in  brazing,  and  also  in 
"blow-pipe  analysis."  When  borax  is*' melted  with 
oxyd  of  chromium,  it  gives  an  emerald  green  ;  with 
oxyd  of  cobalt,  a  deep  blue ;  with  oxyd  of  copper,  a 
pale  green ;  with  oxyd  of  manganese,  a  violet. 

(Page  103. )  PHOSPHIDE  OF  HYDROGEN  is  frequently 
made  by  nearly  filling  a  retort  with  a  strong  solution 


a  Retort  filled  with  solution  of  potash,  with  pieces  of  phosphorus  in  it. 
b  Rings  of  vapor,  from  the  combustion  of  the  phosphuretted  hydrogen. 

of  KO,  and  then  adding  a  few  drops  of  ether  and 
some  small  bits  of  phosphorus.  The  object  of  the 
ether  is  to  prevent  the  explosion  of  the  first  bubbles 
of  gas,  as  they  come  off,  in  the  retort.  The  beak  of 
the  retort  should  dip  under  HO  before  applying  the 
heat. 

The  following  singular  story  is  told  of  the  prob- 
able discovery  of  phosphorus  many  years  before 
that  of  Brandt,  the  reputed  discoverer.  A  certain 
prince  San  Severe,  at  Naples,  exposed  some  human 


244 


ELEMENTAEY  CHEMISTRY. 


skulls  to  the  action  of  several  reagents,  and  then  to 
the  heat  of  a  furnace.  From  the  product  he  obtained 
a  vapor  which  kindled  at  the  approach  of  a  light, 
and  continued  to  burn  aglow  for  months  without  ap- 
parently diminishing  in  weight.  San  Severo  refused 
to  divulge  tJfe  process,  as  he  wished  his  family  vault 
to  be  the  only  one  to  possess  a  "perpetual  lamp" 
the  secret  of  which  he  considered  himself  to  have 
discovered. 

(Page  110.)  SAL-SODA  is  sometimes  called  "  salts 
of  tartar,"  and  when  purified  is  commonly  sold  under 
that  name.  It  is  used  by  barbers  for  cleaning  the 
head,  and  is  a  prominent  constituent  in  many  hair- 
washes  ;  20  or  30  gr.  in  a  gill  of  warm  HO  makes  an 
excellent  solution  for  such  a  purpose. 

(Page  115.)  METALS  OF  THE  ALKALINE  EARTHS. — 
These  are  termed  alkaline  because  they  are  caustic, 
and  earths,  because  they  are  insoluble  in  HO.  The 

annexed  cut  shows  an  im- 
proved form  of  lime-kiln, 
in  which  the  process  is 
continuous.  At  a,  Z>,  c,  d, 
are  the  doors  for  fuel, 
ash-pit,  etc.  The  lime- 
stone is  fed  at  the  top 
from  time  to  time,  while 
the  lime  is  taken  out  at  / 
as  fast  as  formed. 

Concrete  is  a  cement  of 
coarse  gravel  and  water- 

Lime-Kiln. 


APPENDIX.  245 

lime.  It  is  of  great  durability.  Whitewash  is  a  mere 
"  milk  of  lime."  "  Hard  finish"  is  a  kind  of  plaster  in 
which  gypsum  is  used  to  make  the  wall  smooth  and 
hard.  "  Ccdcimining"  is  a  process  of  whitening  walls 
with  a  wash  of  plaster  of  paris,  or  whiting. 

(Page  119.)  PHOSPHATE  OF  LIME. — When  bones 
are  burned,  a  tribasic  phosphate  of  lime  is  formed — 
thus,  3CaO.PO5.  When  this  is  heated  with  SO3, 
the  change  is  as  foUows :  3CaO .  PO5  +  2(SO3 .  HO)  = 
CaO.PO5.2HO  +  2(CaO.SO3).  This  mixture  is 
sometimes  called  the  superphosphate  of  lime,  al- 
though the  term  belongs  properly  only  to  the  CaO . 
PO3.  By  filtering,  the  CaO.SO3  is  removed,  and  the 
superphosphate  is  sold  as  a  fertilizer,  or  may  be 
heated  with  charcoal  to  form  P — thus  : 

2(PO5.3HO)  +  16C  =  2P  +  6H  +  16CO. 

(Page  129.)  When  iron  is  cast  in  large  masses,  the 
metal  has  time  to  crystallize,  and  this  weakens  it 
very  much.  When  immense  cannon  are  cast,  like 
the  Fort  Pitt  gun,  a  stream  of  water  is  allowed  to 
run  through  it  to  hasten  the  cooling  process.  When 
the  melted  iron  is  cooled  in  an  iron  mould,  this  chills 
the  surface  instantly,  and  makes  it  extremely  hard. 
The  product  is  called  " chilled  iron"  and  is  used  for 
safes  and  other  burglar-proof  instruments. 

(Page  133.)  COPPER.-— Both  lead  and  copper  are  fre- 
quently found  native,  the  former  in  Missouri  and  Nor- 
thern New  York ;  the  latter  near  Lake  Superior.  In 
such  cases,  the  extraction  of  the  metal  from  the  spar 
in  which  it  is  imbedded  is  very  simple.  The  ore  is 


246  ELEMENTARY  CHEMISTRY. 

ground  to  powder  in  a  stamp-mill,  and  then, 'by  re- 
peated washing,  during  which  the  metal  sinks  by  its 
superior  specific  gravity,  is  separated  from  the  spar, 
and  is  prepared  for  the  furnace,  where  it  is  melted 
and  cast  into  bars  for  the  market.  The  ore,  contain- 
ing oxyd,  or  carbonate  of  copper,  can  readily  be  re- 
duced by  heating  with  charcoal  and  lime,  as  in  the 
process  of  iron-smelting.  The  sulphurets,  however, 
are  reduced  with  much  greater  difficulty.  They  con- 
tain much  iron  pyrites,  which  must  be  removed. 
They  are  first  roasted,  to  convert  a  part  of  the  sul- 
phurets of  copper  and  iron  into  oxyds.  They  are 
then  smelted,  as  we  have  described  before,  and  the 
iron  mostly  passes  off  in  the  slag,  while  the  copper 
is  reconverted  into  a  sulplmret.  This  is  next 
roasted,  and  lastly  heated  to  so  high  a  temperature, 
that  the  sulphur  leaves  the  copper  as  SO2,  while  the 
melted  metal  is  drawn  off,  ready  for  the  market. 

(Page  138.)  COBALT  is  a  reddish-white  metal,  found 
in  combination  with  arsenic.  It  received  the  name 
cobalus  from  the  miners,  because  its  ore  looked  so 
bright  that  they  thought  they  would  obtain  some- 
thing valuable,  but  by  roasting,  it  crumbled  to  ashes. 
They  therefore  thought  they  were  mocked  by  the 
Kobolds — the  evil  spirits  of  the  mines.  The  oxyd 
of  cobalt  makes  a  beautiful  blue  glass,  which,  when 
ground  fine,  is  called  smalt .  It  is  used  for  tinting  paper, 
and  by  laundry  women  to  give  the  finished  look  to 
cambrics,  linen,  etc.  Its  impure  oxyd,  called  zoffer, 
imparts  the  blue  color  to  common  earthenware  and 


APPENDIX.  247 

porcelain.  The  chloride  (CoCl)  is  used  as  a  sympa- 
thetic ink.  Letters  written  with  a  dilute  solution  of 
it  are  invisible  when  moist  with  the  HO  absorbed 
from  the  air,  but  on  being  dried  at  the  stove,  again 
become  blue.  If  the  paper  be  laid  aside  the  writing 
disappears,  but  may  be  revived  in  the  same  manner. 
A  winter  landscape  may  be  drawn  with  india-ink,  the 
leaves  being  added  with  this  ink.  On  being  brought 
to  the  fire  it  will  bloom  into  the  foliage  of  summer. 

MANGANESE  is  a  hard,  brittle  metal,  resembling 
cast-iron  in  its  color  and  texture.  It  takes  a  beau- 
tiful polish.  Its  binoxyd,  the  black  oxyd  of  man- 
ganese, has  been  spoken  of  as  used  in  the  manufac- 
ture of  O,  Cl,  etc.  By  fusing  four  parts  of  MnO2  and 
three  and  a  half  parts  of  chlorate  of  potash  with 
five  parts  of  KO  dissolved  in  a  little  water,  a  dark 
green  mass  is  obtained  called  " chameleon  mineral" 
If  a  piece  of  this  be  dropped  into  HO,  the  solution 
will  undergo  a  beautiful  change  from  green,  through 
various  shades,  to  purple.  This  is  owing  to  the 
gradual  formation  of  permanganic  acid.  The  change 
may  be  produced  instantaneously  by  a  drop  of  SO3. 

NICKEL  is  a  grayish  metal.  Like  cobalt,  it  is  a 
constituent  of  meteorites.  It  is  mined  in  Pennsylva- 
nia, in  large  quantities,  by  the  United  States  Govern- 
ment, for  making  nickel  cents.  Its  principal  use  is 
in  the  alloy  called  German  silver.  The  salts  of  nickel 
possess  a  beautiful  green  tint.  The  rare  gem  chryso- 
prase  is  colored  with  oxyd  of  nickel. 

BISMUTH  is  a  reddish-white  metal.      It  is  known 


248  ELEMENTARY  CHEMISTRY. 

chiefly  as  an  oxyd,  in  which  form  it  is  much  prized 
as  a  cosmetic  by  those  whose  fading  charms  necessi- 
tate the  use  of  pearl-powder.  This  should  not  be 
indulged  in  by  ladies  intending  to  visit  chemical  la- 
boratories, or  lectures,  as  a  few  bubbles  of  HS  es- 
caping into  the  air  will  change  the  snow-white  com- 
plexion into  a  most  suggestive  black. 

ANTIMONY  was  discovered  by  Basil  Valentine,  a 
monk  of  Germany,  in  the  fifteenth  century.  It  is 
said,  that  to  test  its  properties,  he  first  fed  it  to 
some  hogs  kept  at  the  convent,  and  found  that  they 
thrived  upon  it.  He  then  tried  it  upon  his  fellow- 
monks,  but  perceiving  that  they  died  in  consequence, 
he  forthwith  named  the  new  metal,  in  honor  of  this 
fact,  anti-moine  (anti-monk),  whence  our  term  anti- 
mony is  derived.  • 

Antimony  is  found  as  SbO3.  It  is  a  brittle  bluish- 
white  metal,  with  a  beautiful  laminated  crystalline 
structure.  It  is  used  simply  as  an  alloy  for  type- 
metal,  Britannia-ware,  etc.  Its  test  is  HS,  which 
throws  down  a  brilliant  orange-colored  precipitate. 
Example  :  Melt  a  small  fragment  before  the  blow- 
pipe, and  throw  the  melted  globule  upon  an  inclined 
plane.  It  will  instantly  dart  off  in  minute  spheres, 
each  leaving  behind  a  long  trail  of  smoke. 

(Page  149.)  NITRATE  OF  SILVER  is  much  used  in 
photography.  An  account  of  the  processes  pur- 
sued in  this  art  may  be  interesting  to  some.  The 
daguerreotype  is  named  from  M.  Daguerre,  the  dis- 


APPENDIX.  249 

coverer,  who  received  a  pension  of  6,000  francs  per 
year  from  the  French  government.  A  plate  of  cop- 
per, plated  on  one  side  with  silver,  is  exposed  to  the 
vapor  of  iodine  until  a  compound  of  iodide  of  silver 
is  formed  upon  the  surface.  This  is  extremely  sen- 
sitive to  the  light,  and  for  this  reason  the  process  is 
always  conducted  in  a  dark  closet.  The  plate  is  then 
quickly  carried,  carefully  covered,  to  the  camera, 
and  placed  in  the  focus,  where  the  rays  of  light 
from  the  person  whose  "  picture  is  being  taken"  fall 
directly  upon  it.  These  rays  decompose  the  iodide 
of  silver,  setting  free  the  iodine.  The  amount 
of  this  change  is  directly  proportional  to  the  num- 
ber of  rays  that  are  reflected  from  different  parts  of 
the  person  to  form  the  image  in  the  camera.  A 
white  garment  reflects  all  the  light  that  falls  upon 
it,  so  that  part  of  the  plate  corresponding  will  be 
very  much  changed.  A  black  garment  reflects  no 
light,  so  that  part  will  not  be  changed  at  all.  The 
different  colors  and  shades  reflect  varying  propor- 
tions of  light,  and  so  influence  the  plate  correspond- 
ingly. When  the  plate  is  taken  out  of  the  camera, 
it  is  carefully  covered  again  and  carried  quickly  into 
the  dark  closet.  No  change  can  be  detected  by  the 
eye ;  but  now  expose  it  to  the  vapor  of  mercury,  and 
wherever  the  silver  has  been  freed  from  the  iodine, 
the  Hg  combines  with  it,  forming  a  whitish  amal- 
gam. The  picture  thus  evoked  comes  forth  nearly 
perfect  in  its  lights  and  shades,  but  the  whole  side 


250  ELEMENTARY   CHEMISTRY. 

of  the  plate  is  covered  with  the  iodide  of  silver, 
which  would  blacken  if  we  should  carry  it  out  into 
the  light.  This  must,  therefore,  be  removed,  so  we 
wash  the  plate  with  hyposulphite  of  soda  (NaO.SO2). 
This  dissolves  the  iodide  of  silver,  except  where  it 
has  been  fixed  by  the  mercury,  and  our  picture  needs 
only  washing  and  a  little  paint  on  the  lips  and 
cheeks  to  be  finished.  If,  instead  of  iodine,  we  had 
used  bromine,  the  bromide  of  silver  thus  formed 
would  have  been  much  more  sensitive  to  the  light, 
and  the  picture  could  have  been  taken  much  quicker. 
PHOTOGRAPHY  (light-drawing)  is  founded  essentially 
upon  the  same  principles  as  daguerreotyping.  The 
process  varies  so  much  with  different  operators  that 
only  the  general  outlines  can  be  given.  The  details 
depend  upon  the  quickness,  exactness,  and  skill  of 
the  artist  so  much,  that  the  same  materials  in  differ- 
ent galleries  produce  vastly  different  photographs. 
So  much  skill  has  been  attained  in  this  art,  that  instan- 
taneous views  are  now  taken  by  Anthony  &  Co.,  of 
New  York.  In  their  gallery  the  camera  tube  is  closed 
by  a  slide  which  is  drawn  to  its  place  by  a  heavy 
weight.  The  camera  is  "focused,"  for  instance, 
upon  a  regiment  of  soldiers  moving  up  Broadway, 
and  the  tube  opens  just  as  they  are  raising  their  feet 
for  a  step :  before  they  place  them  on  the  ground 
the  slide  falls  and  the  picture  is  taken — they  are 
photographed  all  standing  on  one  foot,  and  with  the 
other  in  the  air.  The  process  is  as  follows  :  The 
glass  plate  is  (1)  thoroughly  cleansed  ;  (2)  a  small 


APPENDIX.  251 

quantity  of  iodized  collodion*  is  poured  upon  it, 
which  covers  the  glass  with  a  thin  transparent  film, 
when  (3)  it  is  put  in  the  "  nitrate  of  silver  bath,"  t 
where  the  salt  of  silver  in  the  bath  is  absorbed  by 
the  collodion  film  and  changed  to  iodide  of  silver. 
The  plate  is  now  ready  for  the  picture.  After  the 
sitting  the  plate  is  (4)  taken,  carefully  protected  from 
the  light,  to  the  operator's  room.  Here  the  picture 
is  (5)  developed  by  a  solution  of  protosulphate  of 
iron,  with  a  little  acetic  acid  added.  (6)  It  is 
washed  thoroughly ;  (7)  it  is  fixed  with  a  solution 
of  hyposulphite  of  soda  ;  (8)  it  is  washed  and  dried, 
and  (9)  coated  with  amber  varnish  to  preserve  the 
film  from  accidental  injury.  This  completes  the 
"  negative."  From  this  the  pictures  are  (1)  "printed" 
by  placing  the  negative  upon  a  sheet  of  prepared 
paper,!  and  exposing  it  to  the  sun's  rays.  The 
lights  and  shades  are  now  reversed,  and  when 
the  colors  are  sufficiently  deepened  the  picture  is 
(2)  washed,  (3)  toned  in  the  "  toning-bath,"  which 
contains  chloride  of  gold,  and  imparts  the  delicate 
color  to  the  photograph,  (4)  ivasfod,  (5)  fixed,  by 

*  Iodized  collodion  is  composed  of  gun-cotton  dissolved  in 
alcohol  and  ether,  iodized  with  iodide  of  ammonium  and  bromide 
of  cadmium. 

f  The  nitrate  of  silver  bath  contains  nitrate  of  silver,  iodide  of 
silver,  and  water. 

\  The  paper  is  "  sensitized"  by  immersing  it  in  a  solution  of 
clilcride  of  sodium,  and  then  in  one  of  nitrate  of  silver,  thus  fill- 
ing the  pores  of  the  paper  with  the  chloride  of  silver,  which  is 
extremely  sensitive  to  light.  -  .  ,  .  .  f  : 


252  ELEMENTARY  CHEMISTRY. 

placing  the  paper  in  hyposulphite  of  soda,  (6) 
washed,  (7)  dried,  and  (8)  mounted  on  card-board, 
which  completes  the  picture. 

ORGANIC  CHEMISTRY. 

All  organic  substances  contain  carbon,  and  there- 
fore they  have  been  defined  as  the  "  carbon  com- 
pounds." The  phenomena  of  Allotropism  and  Isomer- 
ism  are  evidence  that  the  grouping  of  a  compound 
has  much  to  do  with  its  peculiar  properties.  The 
recent  advances  of  the  science  have  developed  sev- 
eral features  worthy  the  attention  of  the  student. 

A  RADICAL  is  the  base  of  a  system  of  compounds. 
Example  :  Na  forms,  by  union  with  O,  the  oxyd  of 
sodium.  This  combines  with  HO,  forming  the  hydra- 
ted  oxyd  of  sodium,  and  this  again  with  various 
acids.  In  this  way  a  regular  series  of  compounds 
are  produced,  in  which  Na  is  the  starting  point — the 
root,  as  it  were.  Thus  : 

Na Sodium. 

NaO Oxyd  of  sodium. 

NaO.HO Hydrated  oxyd  of  sodium. 

NaO.HO.SOs Sulphate  of  the  hydrated  oxyd  of  sodium. 

NaO.HO.NOs Nitrate  of  the  hydrated  oxyd  of  sodium. 

A  COMPOUND  RADICAL  is  a  compound  that  re- 
sembles an  element  in  all  its  chemical  behavior,  and 
can  be  oxydized  and  transferred  from  one  compound 
to  another,  forming  chlorides,  salts,  etc.,  in  the  same 
manner  as  a  metal,  like  copper  or  iron.  Example  : 
In  the  destructive  distillation  of  C4H3O2  .(alcohol) 


APPENDIX.  253 

and  SO3,  the  acid  takes  out  an  atom  of  HO,  leaving 
C4H5O— common  sulphuric  ether.  Now,  by  taking 
an  atom  of  O  from  this,  there  remains  a  colorless 
gas,  C4H5,  which  has  received  the  name  Ethyl  and 
the  symbol  Ae.  This  plays  the  part  of  an  element, 
and  being  composed  of  two  elements,  is  called  a 
compound  radical.  It  is  the  root  of  a  series  of 
compounds,  thus : 

Ae-Ethyl  (the  radical) C4H6. 

AeO— Oxyd  of  ethyl  (ether) C4H6O. 

AeO.HO— Hydrated  oxyd  of  ethyl  (alcohol) C4H6O.HO. 

AeCl-Hydrochloric  ether C4H6C1. 

AeCy— Cyanide  of  ethyl C4H6Cy. 

AeNO5— Nitrate  of  the  oxyd  of  ethyl   (nitric  ether)....  C4H6O.NO». 

By  this  we  see  that  ether  is  the  oxyd  of  ethyl,  and 
may  be  represented  by  the  symbol  AeO,  while  alco- 
hol is  the  hydrated  oxyd  of  ethyl,  and  may  be  repre- 
sented by  the  corresponding  symbol  AeO .  HO. 

HOMOLOGOUS  bodies  are  those  which  differ  from 
each  other  by  the  constant  addition  of  C2H2,  or  its 
multiple.  By  the  decomposition  of  common  alcohol, 
we  procure  a  series  of  alcohols,  ethers,  and  acids, 
which  differ  from  each  other  by  constantly  adding 
C2H  to  the  preceding  member  of  the  group. 


Alcohols. 

Acids. 

Ethers. 

Methylic.. 

..C2H4Oa 

Formic  

.C2H204 

Methylic. 

...C2H30 

Common  .  . 

..C4H6Oa 

Acetic  

.C4H404 

Common 

...C4H50 

Propylic  .  . 

.  C8H8Oa 

Propionic  .. 

•  C6H604 

CaH70 

Butylic.... 

-.C8H10Oa 

Butylic  

.C8H804 

Butylic    . 

...C8H,0 

Amylic.... 

..C10H12Oa 

Voleric  

-C10H]004 

Amylic    . 

...C10HnO 

C12H14Oa 

Caproic  

.C12H1204 

C12H130 

C14H16Oa 

><Eenanthylic.C14Hi4O4 

C14H150 

Caprylic  .  . 

..C16HJ80, 

Caprylic   ... 

.C16H1804 

Caprylic  . 

...CJ6H170 

254  ELEHENTAKY   CHEMISTRY. 

Many  of  these  various  substances  are  of  no  prac- 
tical value  as  yet,  and  some,  as  seen  above,  are 
merely  hypothetical,  but  will  probably  be  separated 
as  the  others  have  been,  while  all  will  doubtless  be- 
come of  use  in  the  arts.  In  the  art  of  dyeing  they 
have  been  utilized,  and  have  revolutionized  the  entire 
system.  There  are  other  compound  radicals — as 
C2H3,  called  methyl,  symbol  Me — whosa  oxyds  form 
ethers,  and  hydrated  oxyds  alcohols,  as  in  the  case 
of  Ae. 

KAKODYL  is  a  combination  of  Me  with  arsenic — 
thus,  Ae2  As — and  is  a  fearfully  poisonous  liquid.  It 
takes  fire  spontaneously  in  the  air,  producing  HO, 
CO2,  and  AsO3.  It  has  been  used  for  filling  bombs, 
as  a  most  destructive  agent  of  war.  The  homolo- 
gous series  has  been  continued  up  to  melissic  acid 
(CeoHeoOJ,  and  melissic  alcohol  (CgoH^Oa).  The  ex- 
tremes differ  much  in  their  characteristics.  Formic 
acid,  which  is  found  in  red  ants  (formica  rufa),  is 
a  fiery  pungent  acid  that  blisters  the  skin,  while 
melissic  acid  is  a  solid  fat.  The  compound  radical, 
like  any  metal  or  acid,  unites  directly  with  Cl,  I,  H, 
Zn,  S,  and  forms  crystallized  salts. 

SUBSTITUTION  AND  REPLACEMENT. — This  curious  law 
is  stated  thus — that  "one  or  more  elements  of  a 
compound  may  be  replaced  by  any  other  element  or 
group  of  elements  which  are  equivalent  in  their 
chemical  relations,  and  the  chemical  constitution  re- 
main unchanged."  (Silliman.)  For  example :  1st. 
Ammonia  (NH3)  may  be  written  thus :  N  H.  .  JSgw  we 


APPENDIX.  255 

can  substitute  for  an  atom  of  H  a  compound  radical, 

f1  TT 

as  Ae  (ethyl),  and  we  have  N  H4  8,  an  ethyl-ammo- 

H 

nia  ;  or,  displace  two   atoms  of  H,   and  we  have 

TT 

X,  a   bi-ethyl  ammonia;  or,  substituting  three 

f1  TT 

atoms  of  ethyl,  we  have  N  cX,   a   tri-ethyl  ammo- 

C4H6 

nia.  These  three  ammonias  are  called  methylamine, 
bimethylamine,  and  trimethylamine.  They  closely  re- 
semble ammonia,  neutralize  acids,  precipitate  the 
bases  from  salts,  form  white  clouds  with  HC1,  as  in 
the  test  of  ammonia,  and  form  crystallizable  salts  ; 
though  they  steadily  rise  in  boiling  point,  ethylamine 
boiling  at  54.4°,  and  trimethylamine  at  195.8°.  Other 
radicals  yield  other  ammonias,  similar  to  ammonia 
in  odor  and  other  properties. 

2d.  Acetic  acid  (C4H4O4)  may  be  written   c4igo4, 

|H| 

and  the  four  atoms  of  its  H  may  be  replaced  in  suc- 
cession by  three  atoms  of  HC1  (hydrochloric  acid), 

TTfl 

and  form   c4  HCI  o4,  without  at  all  changing  the  acid 

HC1 

character,  and  modifying  but  slightly  its  proper- 
ties. This  new  acid  is  called  chlor-acetic,  symbol 


3d.  The  hydrogen  of  Ammonia  may  not  only  thus 
be  replaced  by  a  compound  radical,  as  ethyle,  amyle, 
etc.,  but  even  by  two  or  more  radicals,  or  by  chlo- 
rine, bromine,  iodine,  zinc,  etc.  Thus,  tartaric  acid 

ITT  I 

may  be  written  C,'H  6W.    Now,  if  we  re- 

!H4 


256  ELEMENTARY  CHEMISTRY. 

place  two  of  the  atoms  of  H  with  two  atoms  of  Zn, 

Zn 

we   have    c8  zn  o,2,  or  C8H4Zn2Oi2 ;   or,  they  can  be 

H4 

replaced  by  one  atom  of  Zn  and  one  of  K — thus, 
c8  K  o12,  and  the  symbol  will  be  C8ZnKH4012.  These 

various  changes  indicate  what  a  vast  field  lies  open 
for  discovery  in  organic  chemistry,  and  the  multi- 
plicity of  possible  compounds.  The  difficulty  of  pro- 
perly classifying  them  is  at  present  insurmountable. 

ALDEHYDE. — Alcohol  (C4H6O2)  is  changed  into 
acetic  acid  (C4H4O4)  by  taking  up  two  atoms  of  O 
from  the  air  to  combine  with  two  elements  of  its  H, 
thus  forming  two  molecules  of  HO.  In  this  there  is 
an  intermediate  step,  during  which  the  two  atoms 
of  H  seem  to  have  left  the  alcohol  in  their  anxiety 
to  combine  with  O,  while  the  alcohol  has  not  yet 
taken  its  O  to  form  the  acetic  acid.  This  interme- 
diate substance  (CJB^Oa)  is  called  aldehyde.  It 
may  be  smelt  by  holding  a  red-hot  coil  of  platinum 
wire  in  a  goblet  containing  a  few  drops  of  alcohol. 

This  experiment,  showing  the  formation  of  alde- 
hyde from  alcohol,  may  be  very  profitably  followed 
by  another,  illustrating  the  change  of  alcohol  into 
acetic  acid.  Place  a  little  platinum  black  in  a  watch 
crystal,  near  a  small  cup  of  alcohol.  Cover  them 
both  with  a  glass  receiver,  and  set  them  in  the  sun- 
light. Soon  a  mist  will  gather,  and  tiny  streams  of 
the  condensed  vapor  of  acetic  acid  will  collect  and 
run  down  the  sides  of  the  glass.  Fresh  air  must  be 
occasionally  admitted  to  oxydize  the  alcohol. 


APPENDIX.  257 

(Page  199.)  The  term  Morphia  is  used  by  those 
who  think  the  substance  an  alkali ;  Morphine,  by 
those  who  deem  it  a  neutral  body. 

OPIUM-EATING  has  become  so  prevalent  in  this 
country  that  a  few  remarks  upon  it  may  not  be  un- 
profitable. The  effect  is  principally  upon  the  ner- 
vous system.  A  delicious  reverie  steals  over  the 
senses.  Every  avenue  of  sensation  is  thrilled  with 
ecstatic  enjoyment.  The  delirious  dream  becomes 
a  vivid  reality.  Eiches  pour  in  abundantly,  and  the 
happy  possessor  revels  in  costly  mansions  with  ele- 
gant appointments  ;  he  wanders  in  gardens  of  tropi- 
cal luxuriance  and  gorgeousness,  where  birds  of  the 
rarest  plumage  sport  in  the  branches,  music  trembles 
in  the  air,  and  perfumes  steal  the  senses.  History, 
poetry,  science,  art — all  the  treasures  of  knowledge 
are  his,  and  the  soul  expands  to  utter  the  most 
brilliant  thoughts.  The  grandest  schemes  present 
themselves  and  prompt  to  the  pursuit  of  most  im- 
possible results.  Every  sense  is  satisfied,  and  the 
whole  man  is  at  perfect  peace.  But,  with  the  effect 
of  the  drug,  the  dream  passes  off,  and  then  there 
comes  a  peculiar  longing,  an  insatiable  craving, 
which  demands  a  repetition  of  the  fascinating 
stimulus.  In  the  course  of  time  the  amount  neces- 
sary to  produce  the  desired  effect  becomes  increased, 
until  at  last,  in  some  cases,  an  ounce  of  laudanum, 
or  ninety  grains  of  the  acetate  of  morphia,  have 
been  consumed  daily.  At  the  first  it  seems  only  a 
•gratification  of  a  harmless  desire,  but  insensibly,  as 


258  ELEMENTABY  CHEMISTEY. 

the  habit  becomes  fixed,  it  develops  an  ungovern- 
able passion.  Step  by  step  the  unsuspecting  victim 
is  led  on,  until  at  last  some  vain  effort  at  release  re- 
veals to  him  the  chains  by  which  he  is  fast  bound  to 
a  fascinating  but  fearful  practice.  Too  often  he 
finds  it  already  too  late.  The  subtle  alkaloid  has 
worked  its  way  into  the  tissues  and  coatings  of 
his  entire  internal  organism.  At  first,  while  com- 
bining with  the  nerves,  it  set  free  a  vast  amount  of 
vitality  and  force,  but  now  it  has  satisfied  itself. 
Already  the  whole  system  is  impregnated  with  it, 
and  no  additional  dose  produces  a  thrill  even  of  the 
delicious  rapture  for  which  the  drug  was  once  so 
eagerly  sought.  If  he  continues  its  use,  a  CERTAIN, 

FEARFUL,  AGONIZING  DEATH  AWAITS  HIM.      If,  resolutely, 

he  summons  his  already  enfeebled  will,  and  com- 
mences the  conflict,  an  agony  of  endurance,  which 
defies  all  description,  is  before  him.  The  whole 
body  must  be  reorganized,  and,  atom  by  atom,  the 
life-energy  of  the  man  drag  out  of  the  flesh  and 
blood  the  corrosive  poison.  For  weeks  and  months 
he  endures  the  terrible  torture,  racked  by  intensest 
agony  in  every  nerve  and  fibre,  with  visions  of 
horror  filling  the  mind.  At  last,  the  constitution 
conquers  or  the  man  dies.  Yet  this  fearful  struggle 
is  better  than  apathy,  for  the  victim  of  this  habit 
moves  on  directly  to  one  fate — the  opium-eater's 
grave. 

This  frightful  but "  o'er  true"  picture  of  the  opium- 


APPENDIX.  259 

eater's  fate  should  deter  all  who  need  it  from  thought- 
lessly using  paregoric,  laudanum,  morphine,  or 
opium,  in  any  form,  lest  they,  too,  may  come  also  to 
such  a  doom.  In  almost  every  case  it  is  taken  first 
as  a  sedative  from  pain  or  fatiguing  labor,  with  no 
thought  of  becoming  addicted  to  its  use.  But  so 
insinuating  is  it  that  the  victim  forms  the  habit  ere 
he  is  aware,  and  only  knows  he  is  a  slave  when  for 
some  reason  he  attempts  to  cease  the  customary  dose 
and  finds  himself  bound  to  a  bitter  servitude. 

CIRCULATION  OF  MATTER. — The  truth  that  matter 
passes  from  the  animal  back  to  the  vegetable,  and 
from  the  vegetable  to  the  animal  kingdom  again,  re- 
ceived a  curious  illustration  not  long  since,  as  stated 
in  the  Hartford  Press.*  For  the  purpose  of  erecting 
a  suitable  monument  in  memory  of  Roger  Williams, 
the  founder  of  Rhode  Island,  his  private  burying- 
ground  was  searched  for  the  graves  of  himself  and 
wife.  It  was  found  that  everything  had  passed  into 
oblivion.  The  shape  of  the  coffins  could  only  be 
traced  by  a  black  line  of  carbonaceous  matter.  The 
rusted  hinges  and  nails,  and  a  round  wooden  knot, 
alone  remained  in  one  grave  ;  while  a  single  lock  of 
braided  hair  was  found  in  the  other.  Near  the 
graves  stood  an  apple-tree.  This  had  sent  down  two 
main  roots  into  the  very  presence  of  the  coffined 

*  The  author  has  in  his  possession  a  letter,  from  a  gentleman 
who  was  present  at  the  opening  of  this  grave,  attesting  the  truth 
of  this  singular  statement. 


260  ELEMENTABY  CHEMISTRY. 

dead.  The  larger  root,  pushing  its  way  to  the  pre- 
cise spot  occupied  by  the  skull  of  Roger  Williams, 
had  made  a  turn  as  if  passing  around  it,  and  followed 
the  direction  of  the  backbone  to  the  hips.  Here  it 
divided  into  two  branches,  sending  one  along  each 
leg  to  the  head,  when  both  turned  upward  to  the 
toes.  One  of  these  roots  formed  a  slight  crook  at 
the  knee,  which  made  the  whole  bear  a  striking  re- 
semblance to  the  human  form.  There  were  the 
graves,  but  their  occupants  had  disappeared;  the 
bones  even  had  vanished.  There  stood  the  thief — 
the  guilty  apple-tree — caught  in  the  very  act  of  rob- 
bery. The  spoliation  was  complete.  The  organic 
matter — the  flesh,  the  bones,  of  Roger  Williams — 
had  passed  into  an  apple-tree.  The  elements  had 
been  absorbed  by  the  roots,  transmuted  into  woody 
fibre,  which  could  now  be  burned  as  fuel,  or  carved 
into  ornaments ;  had  bloomed  into  fragrant  blossoms, 
which  had  delighted  the  eye  of  passers-by,  and  scat- 
tered the  sweetest  perfume  of  spring ;  more  than 
that — had  been  converted  into  luscious  fruit,  which, 
from  year  to  year,  had  been  gathered  and  eaten. 
How  pertinent,  then,  is  the  question,  "Who  ate 
Eoger  Williams?" 

Shakespeare  expresses  the  same  chemical  thought 
when  he  says : 

"  Imperious  Csesar,  dead  and  turned  to  clay, 
Might  stop  a  hole  to  keep  the  wind  away. 
Oh!  that  the  earth  which  kept  the. world  in  awe 
Should  patch  a  wall  to  expel  the  winter's  flaw!" 


APPENDIX.  261 


Or,  again,  when  he  makes  Ariel  sing  : 

"  Full  fathom  five  thy  father  lies : 
Of  his  bones  are  coral  made ; 

Those  are  pearls  that  were  his  eyes ; 
Nothing  of  him  that  doth  fade 
But  doth  suffer  a  sea  change 
Into  something  rich  and  strange." 


INDEX. 


137 
195 
92 
165 
64 
140 
181 
73 
182 
88 
73 
91 

189 
164 

129 
13 
247 
166 
88 
81 
80 
210 
60 
93 
92 
150 
212 
123 
90 
192 
209 

200 
115 
64 
81 
203 
142 
192 
192 
188 
195 
169 
54 
100 
71 
72 
20S 
19 
159 
159 
B7 

*    'Carbonate'..".!'.! 

134 
130 
142 
162 

209 
173 
163 
147 
72 

78 
90 
158 
55 
172 
82 
81 
202 

9 
11 
10 
163 
191 
90 
175 

183 
170 
207 
68 
51 
75 
90 
218 
176 
73 
150 

134 
57 
72 
83 
72 
208 
150 
111 
122 
208 
209 
184 
145 
56 
158 
158 
195 
191 
162 
106 
197 
118 

I 

127 
253 

4     Boracic  

Bessemer's  process  
Binary  compounds  
Bismuth  

Corrosive  sublimate  
Cotton 

4     Carbolic  

4     Chromic 

Bitumen  

Cream  of  tartar  

4     Citric 

Bleaching-powder  
Blow-pipe  

1     Fulminic  

Cupellation  

4     Hydrochloric  
1     Hydrocyanic  

Bones  

Davy's  Safety  Lamp.... 
Disinfectant  
Dextrine  

Bone-black 

Borax    

1     Hydrosulphuric.  .  . 

99 
209 
181 
183 
88 
37 
38 
183 
179 
102 
73 
163 
93 
183 
96 
96 
181 
180 
13 

•B 

206 
174 
176 

SS 

234 
197 
150 
156 
123 
123 
121 
152 
141 
195 
114 
39 
41 
41 
41 
165 
60 
248 

£ 

139 
166 
11 
82 

193 

S§ 

Boron  
Brass 

4     Malic  
4     Margaric 

Bread 

Diastase 

Brick  

Diffusion,  Law  of.  
Drummond  Light  

4      Muriatic 

Bromine  

44     Nitric  
44     Nitrous 

Butter 

Elements  
Symbols  
Equivalents  

"     Oleic 

Caffeine  

4<     Oxalic. 

"     Phosphoric  
4      Prussic 

Calcium  

Chloride  ... 
44       Light  
Calico-printing  
Calomel 

44     Pyroligneous  
44     Silicic 

«•     Stearic 

Ethers            .     .     .. 

41     Sulphuric  
1     Sulphurous  
1     Tannic  

Fats  

Camphor  
Candles  

Fermentation  

44     Tartaric  
Acids 

Fibrin 

Fire-damp    
Fish,  Breathing  of  

"     Vegetable  
Air  
Albumen  

Carbon     ... 

44      Bisulphide  
Carbonic  oxyd  
Carburetted  hydrogen.  .  . 
Casein  
Catalysis  

Fluorine  

Alcohol 

Food,  Varieties  of,  etc  .  . 
Fusel  oil  
Fulminates  

14     Amylic 

Alkalies  ] 
Metals  of  
Manufacture  of. 
Alkaloids  

Cells 

Fusible  Metal 

Cellulose 

Galena    

Charcoal  

Alloys  
Allotropism  

Cheese  
Chemical  affinity  

208 
9 
153 

1 

212 
86 
176 
68 
140 
140 
177 
122 
61 
165 
164 
246 
204 
62 
163 
80 
73 
168 
133 
134 

Gas,  Carbon  :• 

44    Illuminating  
44    Diffusion  of.  
"    Olefiant     

Alum 

Chemistry,  Organic  
Chemistry  of  candle  
"           lamp  
14           fire  

Aluminum  

Gelatin  

44        Bronze  

German  silver  

44       Domestic  .... 
Chlorine 

Glass 

Amber  

Glazing  of  pottery-  ware. 
Gluten  
Glue 

Ammonium  

Chloroform  

44        Carbonate  .... 
44        Muriate  
Chloride  
Aniline  

Chrome  yellow  

Gold 

Cider  .  .  . 

Graphite    

Clay  
Coal 

Gum  
44  Arabic 

Animal  charcoal  
Antimony  (App.) 

44    oil 

44    tar  

44  Lac              .     .. 

Arsenic  

Cobalt  (App.) 
Cochineal  
Coke 

Arsenuretted  hydrogen.  . 

Atomic  theory  
Atmosphere  

Collodion  
Compound  blow-pipe  — 
Combustion  

Haloids  

Heat 

Barium,  Chloride  
Bases  

^^Acetaie.:: 

Hematite  
Hom^losrous  Series  (App. 

264 


INDEX. 


Hydrates  
Hydraulic  cement  
Hydro-carbons  

49 
116 
75 
42 
99 
72 

71 
45 

195 

"W 

Naphtha  
Nascent  state  
Nitre 

166 
40 

"S 

30 

164 
190 
176 
174 
166 
189 
191 
190 
164 
96 
183 
183 
197 
IV? 

Sal-ammoniac  

41 
108 
110 
121 
180 
110 
110 
14 
218 
106 
159 
180 
194 
151 
93 
146 
147 
127 
185 
111 
233 
107 
107 
108 
93 
59 
79 
131 
117 
157 
183 
129 
199 
169 
167 
136 
95 
99 
11 

181 
164 
181 
110 
210 
132 
161 
150 
204 

134 
239 
177 

£ 

132 
96» 

47 
116 
189 
194 
118 
173 
159 
163 
163 

171 
131 

Salt,  Common  
"    Glauber  
"    Epsom  
"    Rochelle  
"    of  tart  ar  (sal-soda)  . 
Sal-soda  
Salts  
Salted  meat  ,  
Saltpetre..*.  .. 

Sulphuretted.  . 
"         Heavy  carbu-  ) 
retted  5 
"        Light    carbu-  ) 
retted.  j 
"        Tones  

Nitrogen  

Oil,  Bitter  almonds  
"  Castor  
"  Fusel  
"  Juniper  berries  

Secretion 

Seidlitz  powders  
Shellac  
Shot  .  .  . 

Indigo  

"  Lemon  

Ink   .  

!«•' 

»  Olive  

"  Printers'  
"  Red 

189 
205 
91 
144 
125 
130 
130 
156 
60 

60 
34 
134 
136 
136 
136 
137 
56 
136 
136 
181 
159 
115 
88 
117 
118 
119 
119 
80 
162 
205 
136 
147 
184 

204 
119 
171 
71 
102 
16 
141 

"  Turpentine  
"  of  vitriol 

Silicon..., 

Silver 

Iodine 

Oils       

"    Nitrate 

Olein  
Opium  

Smelting  
Soap 

Iron.  .  .    . 

"  Sulphuret. 

Oreide  

soda:::::':   :  

"  Sulphate  

Organic  chemistry  

153 

197 
202 

155 
144 

18 
29 

160 
165 
162 
105 
62 
159 
73 
94 
199 
165 
103 
101 
250 
164 
84 
118 
116 
144 
56 
104 
105 
105 
106 
106 
73 
122 
179 
17 
56 
210 

141 
146 
199 

142 
208 
194 
194 

158 
lOfi 

"    Carbonate  
"    Sulphate  
Sodium    . 

bases  
"       coloring   prin-  ) 
ciples  } 
Organogens  

Ivory-black  ...   . 

Lampblack  

"      Chloride  of  
Soldering  .  .  . 

Laughing-gas  
Lead 

Soot. 

Spontaneous  combustion 
Spelter  

"    Acetate  of 

Ozone  

"    Carbonate.. 

Paper  
Paraffine  

Stalactites  ... 

"    Sugar  of.  
"    Tree  
"    Black  
"    Ked  
11    White 

Starch  

Stearin.  .  .  . 
Steel  
Strychnine  

Pearlash  
Peat  
Pectine  
Percussion  caps  

Sugar  grape  
cane.  .  .  . 

Leather  

Lignine.  .  .  . 

"     oflead  

Lime 

Petrifactions 

"    Chloride 

Sulphuretted  hydrogen  . 
Symbols  ... 

u    Carbonate  
"    Sulphate  
"    Phosphate  
"    Superphosphate  .  .  . 
T."    Light  
Linen    .  . 

Phosphorescence  
Phosphorus  
Photography  (App.) 
Pitch  
Plants  in  the  room  
Plaster  of  Paris  
Plastering  
Platinum  

Tannin..., 

Tar 

Tartar  emetic  
'     Salts  of  (sal-soda) 
Tea  

Litmus  
Litharge  
Lunar  caustic.  .  .  . 

Tin  

Turpentine  

Lye  

Plumbago  

Type-metal  

Madder  

Potassium  

Tyrian  purple  

Potash  

Verdigris 

Malt  .  .  . 

"     Bicarbonate  
"     Nitrate  
"     Prussiate  of.  
Pottery  

Ventilation  (App.)  ...   . 
Vinegar  

Marsh-gas.  .  .  . 

Matches  
Mathematics  of  chemistry 

Vitriol,  Green  

"       Blue... 
"       White  
"      Oil  of 

"      Chloride  of  ... 
Metals  

142 
104 
104 
121 
115 
125 
209 
143 
44 
167 
202 
199 
115 
63 
45 

Problems 

Water  

"     Alkalies  
'     Earths.  . 

Putrefaction  

Quicksilver  

Water-lime  
Wax  
"  Sealing  

11     Alkaline  earths  .  . 
"     Heavy  
Milk  .... 

Quartation  
Quinine 

Whiting 

Mirror  

Red  precipitate 

Wines 

Mixed  gases  
Molasses  
Mordant  
Morphia  

Woody  fibre  
"         Distillation  of 
Wood-tar  

Yeast 

Rennet  
Resin  

Mortar  

Sago 

Muck  

Zinc... 

Musical  tones  

,Saleratus  .  .  . 

National  Series  of  Standard  School-Hooks. 


ORTHOGRAPHY  AND  READING. 


FATIOFAL  SEMES 

OF 

READERS    AND     SPELLERS, 

BY  PAEKER  &  WATSOK 


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This  unrivaled  series  has  acquired  for  itself  during  a  very  few  years  of  publication, 
a  reputation  and  circulation  never  before  attained  by  a  series  of  school  readers  in  the 
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The  salient  features  of  these  works  which  have  combined  to  render  them  so  populai 
may  be  briefly  recapitulated  as  follows  ; 

1,  THE  WORD  METHOD  SYSTEM— This  famous  progressive  method  for  young 
children  originatad  and  was  copyrighted  with  these  books.     It  constitutes  a  process  by 
which  the  beginner  with  words  of  one  letter  is  gradually  introduced  to  additional  lists 
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mastery  of  the  more  difficult  constructions.     This  is  justly  regarded  as  one  of  the 
most  striking  modern  improvements  in  methods  of  teaching. 

2,  TREATMENT   OF  PRONUNCIATION.— The  wants  of  the  youngest  scholars 
in  this  department  are  not  overlooked.    It  may  be  said  that  from  the  first  lesson  tho 
student  by  this  method  need  never  be  at  a  loss  for  a  prompt  and  accurate  render- 
ing of  every  word  encountered. 

3,  ARTICULATION    AND    ORTHOEPY   are  recognized  as  of  primary  im- 
portance. 

3  (Over.) 


The  National  Series  of  Standard  School-Books. 

ORTHOGRAPHY  AND    READING-Continued. 

4,  PUNCTUATION  is  inculcated  by  a  series  of  interesting  reading  lessons,  the 
simple  perusal  of  which  suffices  to  fix  its  principles  indelibly  upon  the  mind. 

5,  ELOCUTION.    Each  of  the  higher  Readers  (3d,  4th  and  5th)  contains  elaborate, 
echolarly,  and  thoroughly  practical  treatises  on  elocution.     This  feature  alone  has 
secured  for  the  series  many  of  its  warmest  friends. 

6,  THE  SELECTIONS  are  the  crowning  glory  of  the  series.    Without  exception 
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style.     So  acceptable  has  the  taste  of  the  authors  in  this  department  proved,  not  only 
to  the  educational  public  but  to  the  reading   community  at  large,  that  thousands  of 
copies  of  the  Fourth  and  Fifth  Readers  have  found  their  way  into  public  and  private 
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ature, for  reference  as  well  as  perusal. 

7,  ARRANGEMENT,    The  exercises  are  so  arranged  as  to  present  constantly  al- 
ternating practice  in  the  different  styles  of  composition,  while  observing  a  definite 
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the  Third  Reader. 

10,  THE  GRADATION  is  perfect.    Each  volume  overlaps  its  companion  pre- 
ceding or  following  in  the  series,  so  that  the  scholar,  in  passing  from  one  to  another, 
is  barely  conscious,  save  by  the  presence  of  the  new  book,  of  the  transition. 

11,  THE  PRICE  is  reasonable.     The  books  were  not  trimmed  to  the  minimum 
of  size  in  order  that  the  publishers  mighc  be  able  to  denominate  them  "the  cheapest 
in  the  market,"  but  were  made  large  enough  to  cover  and  suffice  for  the  grade  indi- 
cated by  the  respective  numbers.    Thus  the  child  is  not  compelled  to  go  over  las  First 
Reader  twice,  or  be  driven  into  the  Second  before  he  is  prepared  for  It.     The  compe- 
tent teachers  who  compiled  the  series  made  each  volume  just  what  it  should  be,  leav- 
ing it  for  their  brethren  who  should  use  the  books  to  decide  what  constitutes  true 
cheapness.    A  glance  over  the  books  will  satisfy  any  one  that  the  same  amount  of 
matter  is  nowhere  furnished  at  a  price  more  reasonable.     Besides  which  another  con- 
sideration enters  into  the  question  of  relative  economy,  namely,  the 

12,  BINDING,    By  the  use  of  a  material  and  process  known  only  to  themselves, 
in  common  with  all  the  publications  of  this  house,  the  National  Readers  are  warranted 
to  out-last  any  with  which  they  may  be  compared— the  ratio  of  relative  durability  be- 
ing in  their  favor  as  two  to  one. 

4 


The  National  Series  of  Standard  School-JBoofcs. 

SCHOOL-ROOM    CARDS, 

To  Accompany  the  National  Readers. 
Eureka  Alphabet  Tablet *i  50 

Presents  the  alphabet  upon  the  Word  Method  System,  by  which  the 
child  will  learn  the  alphabet  in  nine  days,  and  make  no  small  progress  in 
reading  ana  spelling  in  the  same  time. 

National  School  Tablets,  10  Nos *7  50 

Embrace  reading  and  conversational  exercises,  object  and  moral  les- 
sons, form,  color,  &c.  A  complete  set  of  these  large  and  elegantly  illus- 
trated Cards  will  embellish  the  school-room  more  than  any  other  article 
of  furniture. 


READING. 


Fowle's  Bible  Reader $100 

The  narrative  portions  of  the  Bible,  chronologically  and  topically  ar- 
ranged, judiciously  combined  with  selections  from  the  Psalms,  Proverbs, 
and  other  portions  which  inculcate  important  moral  lessons  or  the  great 
truths  of  Christianity.  The  embarrassment  and  difficulty  of  reading  the 
I'.i  ie  itself,  by  course,  as  a  class  exercise,  aro  obviated,  and  its  use  made 
feasible,  by  this  means. 

North  Carolina  First  Reader 50 

North  Carolina  Second  Reader 75 

North  Carolina  Third  Reader l  oo 

Prepared  expressly  for  the  schools  of  this  State,  by  C.  H.  Wiley,  Super- 
intendent of  Common  Schools,  and  F.  M.  llubbard,  Professor  of  Litera- 
ature  in  the  State  University. 

Parker's  Rhetorical  Reader .......  l  oo 

Designed  to  familiarize  Readers  with  the  pauses  and  other  marks  in 
general  use,  and  lead  them  to  the  practice  of  modulation  and  inflection  of 
the  voice. 

Introductory  Lessons  in  Reading  and  Elo- 
cution      75 

Of  similar  character  to  the  foregoing,  for  less  advanced  classes. 

High  School  Literature l  50 

Admirable  self-ctions  from  a  long  list  of  the  world's  best  writers,  for  ex- 
ercise in  reading,  oratory,  and  composition.  Speeches,  dialogues,  and 
model  letters  represent  the  latter  department. 

5 


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ORTHOGRAPHY" 

SMITH'S    SERIES 

Supplies  a  speller  for  every  class  in  graded  schools,  and  comprises  the  most  com- 
"  plete  and   excellent  treatise    on    English   Orthography  and  its  companion 
branches  extant. 

1.  Smith's  Little  Speller $25 

First  Round  in  the  Ladder  of  Learning. 

2.  Smith's  Juvenile  Definer so 

Lessons  composed  of  familiar  words  grouped  with  reference  to  similar 
signification  or  use,  and  correctly  spelled,  accented,  and  defined. 

3.  Smith's  Grammar-School  Speller ....     60 

Familiar  words,  grouped  with  reference  to  the  sameness  of  sound  of  syl- 
lables differently  spelled.  Also  definitions,  complete  rules  for  spelling  and 
formation  of  derivatives,  and  exercises  in  false  orthography. 

4.  Smith's  Speller  and  Defmer's  Manual    •     90 

A  complete  School  Dictionary  containing  14,000  words,  with  various 
other  useful  matter  in  the  way  of  Rules  and  Exercises. 

5-  Smith's  Hand-Book  of  Etymology  .    .   .  1  oo 

The  first  and  only  Etymology  to  recognize  the  Anglo-Saxon  our  mother 
tongue;  containing  also  full  lists  of  derivatives  from  the  Latin,  Greek, 
Gaelic,  Swedish,  Norman,  &c.,  &c. ;  being,  in  fact,  a  complete  etymology 
of  the  language  for  schools. 

Sherwood's  Writing  Speller 18 

Sherwood's  Speller  and  Definer 18 

Sherwood's  Speller  and  Pronouncer    ...     18 

The  Writing  Speller  consists  of  properly  ruled  and  numbered  blanks 
to  receive  the  words  dictated  by  the  teacher,  with  space  for  remarks  and 
corrections.  The  other  volumes  may  be  used  for  the  dictation  or  ordinary 
class  exercises. 

Price's  English  Speller *15 

A  complete  spelling-book  for  all  grades,  containing  more  matter  than 
"Webster,"  manufactured  in  superior  style,  and  sold  at  a  lower  price — 
consequently  the  cheapest  speller  extant. 

Northend's  Dictation  Exercises 75 

Embracing  valuable  information  on  a  thousand  topics,  communicated 
in  such  a  manner  as  at  once  to  relieve  the  exercise  of  spelling  of  its  usual 
tedium,  and  combine  it  with  instruction  of  a  general  character  calculated 
to  profit  and  amuse. 

Wright's  Analytical  Orthography    ....     30 

Tliis  standard  work  is  popular,  because  it  teaches  the  elementary  sounds 
in  a  plain  and  philosophical  manner,  and  presents  orthography  and  or- 
thoepy in  an  easy,  uniform  system  of  analysis  or  parsing. 

Fowle's  False  Orthography 5° 

Exercises  for  correction. 

Page's  Normal  Chart .    .*3  75 

The  elementary  sounds  of  the  language  for  the  school-room  walls. 

6 


The  National  Series  of  Standard  School-Books. 

ENGLISH    GRAMMAR. 
CLARK'S   DIAGRAM   SYSTEM. 

Clark's  First  Lessons  in  Grammar    ...     50 

Clark's  English  Grammar 1  oo 

Clark's  Key  to  English  Grammar  .  .  .  .  *75 
Clark's  Analysis  of  the  English  Language  •  60 
Clark's  Grammatical  Chart .*3  75 

The  theory  and  practice  of  teaching  grammar  in  American  schools  is 
meeting  with  a  thorough  revolution  from  the  use  of  this  system.  While 
the  old  methods  offer  proficiency  to  the  pupil  only  after  much  weary 
plodding  and  dull  memorizing,  this  affords  from  the  inception  the  ad- 
vantage of  practical  Object  Teaching,  addressing  the  eye  by  means  of  il- 
lustrative figures  ;  furnishes  association  to  the  memory,  its  most  power- 
ful aid,  and  diverts  the  pupil  by  taxing  his  ingenuity.  Teachers  who  are 
using  Clark's  Grammar  uniformly  testify  that  they  and  their  pupils  find 
it  the  most  interesting  study  of  the  school  course. 

Like  all  great  and  radical  improvements,  the  system  naturally  met  at 
first  with  much  unreasonable  opposition.  It  has  not  only  outlived  the 
greater  part  of  this  opposition,  but  finds  many  of  its  warmest  admirers 
among  those  who  could'  not  at  first  tolerate  so  radical  an  innovation.  All 
it  wants  is  an  impartial  trial,  to  convince  the  most  skeptical  of  its  merit. 
No  one  who  has  fairly  and  intelligently  tested  it  in  the  school-room  has 
ever  been  known  to  go  back  to  the  old  method.  A  great  success  is  al- 
ready established,  and  it  is  easy  to  prophecy  that  the  day  is  not  far  dis- 
tant when  it  will  be  the  only  system  of  teaching  English  Grammar.  As 
the  SYSTEM  is  copyrighted,  no  other  text-books  can  appropriate  this  ob- 
vious and  great  improvement. 

Welch's  Analysis  of  the  English  Sentence  .  1  25 

Remarkable  for  its  new  and  simple  classification,  its  method  of  treat- 
ing connectives,  its  explanations  of  the  idioms  and  constructive  laws  of 
the  language,  &c. 

n 

POLITICAL    SCIENCE. 

«  «^  » 

Young  Citizen's  Catechism 75 

Explaining  the  duties  of  District,  Town,  City,  County,  State,  and 
United  States  Officers,  with  rules  for  parliamentary  and  commercial  busi 
ness — that  which  every  future  "  sovereign"  ought  to  know,  and  so  few  are 
taught. 

Mansfield's  Political  Manual 1  50 

This  is  a  complete  view  of  the  theory  and  practice  of  the  General  and 
State  Governments  of  th«  United  States,  designed  as  a  text-book.  The 
author  is  an  esteemed  and  able  professor  of  constitutional  law.  widely 
known  for  his  sagacious  utterances  in  matters  of  statecraft  through  tho 
public  press.  Recent  events  teach  with  emphasis  the  vital  necessity  that 
the  rising  generation  should  comprehend  the  noble  polity  of  the  American 
government,  that  they  may  act  intelligently  when  endowed  with  a  voice 
in  it. 

7 


The  National  Series  of  Standard  School-Books. 


GEOGRAPHY. 


THE 

NATIONAL  GEOGRAPHICAL  SYSTEM, 


I.  Monteith's  First  Lessons  in  Geography,  %   38 

II.  Monteith's  Introduction  to  the  Manual,  •     75 

III.  Monteith's  New  Manual  of  Geography,  .  1  20 

IV.  Monteith's  Physical  &  Intermediate  Geog.  2  oo 

V.  McNally's  System  of  Geography,    •    •    •  2  25 

The  only  complete  course  of  geographical  instruction.  Its  circulation 
is  almost  universal — its  merits  patent.  A  few  of  the  elements  of  its  popu- 
larity are  found  in  the  following  points  of  excellence. 


1.  PEACTICAL    OBJECT    TEACHING-,    The  infant  scholar  is  first  introduced 
to  a  picture  whence  he  may  derive  notions  of  the  shape  of  the  earth,  the  phenomena 
of  day  and  night,  the  distribution  of  land  and  water,  and  the  great  natural  divisions, 
which  mere  words  would  fail  entirely  to  convey  to  the  untutored  mind.     Other  pic- 
tures follow  on  the  same  plan,  and  the  child's  mind  is  called  upon  to  grasp  no  idea 
without  the  aid  of  a  pictorial  illustration.     Carried  on  to  the  higher  books,  this  system 
culminates  in  No.  4,  where  such  matters  as  climates,  ocean  currents,  the  winds,  pecu- 
liarities of  the  earth's  crust,  clouds  and  rain,  are  pictorially  explained  and  rendered 
apparent  to  the  most  obtuse.    The  illustrations  used  for  this  purpose  belong  to  the 
highest  grade  of  art. 

2,  CLEAE,   BEAUTIFUL,  AND  CORBECT   MAPS,    In  the  lower  numbers 
the  maps  avoid  unnecessary  detail,  while  respectively  progressive,  and  affording  the 
pupfl  new  matter  for  acquisition  each  time  he  approaches  in  the  constantly  enlarging 
circle  the  point  of  coincidence  with  previous  lessons  in  the  more  elementary  books. 
In  No.  4,  the  maps  embrace  many  new  and  striking  features.     One  of  the  most 
effective  of  these  is  the  new  plan  for  displaying  on  each  map  the  relative  sizes  of 
countries  not  represented,  thus  obviating  much  confusion  which  has  arisen  from  the 
necessity  of  presenting  maps  in  the  same  atlas  drawn  on  different  scales.    The  maps 
of  No.  5  have  long  been  celebrated  for  their  superior  beauty  and  completeness.     This 
is  the  only  school-book  in  which  the  attempt  to  make  a  complete  atlas  also  clear  and 
distinct,  has  been  successful.    The  map  coloring  throughout  the  series  is  also  notice- 
able.   Delicate  and  subdued  tints  take  the  place  of  the  startling  glare  of  inharmonious 
colors  which  too  frequently  in  such  treatises  dazzle  the  eyes,  distract  the  attention, 
and  serve  to  overwhelm  the  names  of  towns  and  the  natural  features  of  the  landscape. 

8 


The  National  Series  of  Standard  School-Books. 


GEOGRAPHY-Continued, 

3.  THE  VARIETY  OF  MAP  EXERCISE,    Starting  each  time  from  a  different 
basis,  the  pupil  in  many  instances  approaches  the  same  fact  no  less  than  six  times, 
thus  indelibly  impressing  it  upon  his  memory.    At  the  same  time  this  system  is  not 
allowed  to  become  wearisome — the  extent  of  exercise  on  each  subject  being  graduated 
by  its  relative  importance  or  difficulty  of  acquisition. 

4.  THE  CHARACTER  AND   ARRANGEMENT  OF   THE  DESCRIPTIVE 
TEXT,     The  cream  of  the  science  has  been  carefully  culled,  unimportant  matter  re- 
jected, elaboration  avoided,  and  a  brief  and  concise  manner  of  presentation  cultivated. 
The  orderly  consideration  of  topics  has  contributed  greatly  to  simplicity.    Due  atten 
tion  is  paid  to  the  facts  in  history  and  astronomy  which  are  inseparably  connected 
with,  and  important  to  the  proper  understanding  of  geography— and  such  only  are 
admitted  on  any  terms.    In  a  word,  the  National  System  teaches  geography  as  a 
science,  pure,  simple,  and  exhaustive. 

5.  ALWAYS  UP   TO  THE   TIMES,    The  authors  of  these  books,  editorially 
speaking,  never  sleep.     No  change  occurs  in  the  boundaries  of  countries,  or  of  coun- 
ties, no  new  discovery  is  made,  or  railroad  built,  that  is  not  at  once  noted  and  re- 
corded, and  the  next  edition  of  each  volume  carries  to  every  school-room  the  new  or- 
der of  things. 

6.  SUPERIOR  GRADATION.     This  is  the  only  series  which  furnishes  an  avail- 
able volume  for  every  possible  class  in  graded  schools.     It  is  not  contemplated  that  a 
pupil  must  necessarily  go  through  every  volume  in  succession  to  attain  proficiency. 
On  the  contrary,  two  will  suffice,  but  three  are  advised ;  and  if  the  course  will  admit, 
the  whole  series  should  be  pursued.    At  all  events,  the  books  are  at  hand  for  selection, 
and  every  teacher,  of  every  grade,  can  find  among  them  one  exactly  suited  to  his  class. 
The  best  combination  for  those  who  wish  to  abridge  the  course  consists  of  Nos.  1,  3, 
and  5,  or  where  children  are  somewhat  advanced  in  other  studies  when  they  com- 
mence geography,  Nos.  2,  3,  and  5.    Where  but  two  books  are  admissible,  Nos.  2  and 
4,  or  Nos.  3  and  5,  are  recommended. 

7.  FORM  OF  THE  VOLUMES  AND  MECHANICAL  EXECUTION,    The 
maps  and  text  are  no  longer  unnaturally  divorced  in  accordance  with  the  time-hon- 
ored practice  of  making  text-books  on  this  subject  as  inconvenient  and  expensive  as 
possible.     On  the  contrary,  all  map  questions  are  to  be  found  on  the  page  opposite  the 
map  itself,  and  each  book  is  complete  in  one  volume.     The  mechanical  execution  is 
unrivalled.    Paper  and  printing  are  everything  that  could  be  desired,  and  the  bind- 
ing is— A.  8.  Barnes  and  Company's. 


Ripley's  Map  Drawing $*  25 

This  system  adopts  the  circle  as  its  basis,  abandoning  the  processes  by 
triangulation,  the  square,  parallels,  and  meridians,  &c.,  which  have  been 
proved  not  feasible  or  natural  in  the  development  of  this  science.  Suc- 
cess seems  to  indicate  that  the  circle  "  has  it." 

National  Outline  Maps 

For  the  school-room  walls.    In  preparation. 

9 


The  National  Series  of  Standard  School-Books. 


MAT  HEM  A  T  I  C  S  . 


ARITHMETIC. 

1.  Davies'  Primary  Arithmetic    ...........  $25 

2.  Davies'  Intellectual  Arithmetic  .........      40 

3.  Davies'  Elements  of  Written  Arithmetic     ......      50 

4.  Davies'  Practical  Arithmetic    ...........  1  00 

Key  to  Practical  Arithmetic  ........  *1  00 

5.  Davies'  University  Arithmetic  ...........  1  50 

Key  to  University  Arithmetic     .......  «1  50 

ALGEBRA. 

1.  Davies'  New  Elementary  Algebra    .........  1  25 

Key  to  Elementary  Algebra  ........  *1  25 

2.  Davies'  University  Algebra     ...........  1  75 

Key  to  University  Algebra     ........  *1  75 

3.  Davies'  Bourdon's  Algebra    ...........  2  50 

Key  to  Bourdon's  Algebra    ........  *2  50 

GEOMETRY. 

1.  Davies'  Elementary  Geometry  and  Trigonometry  .    .    .  1  50 

2.  Davies'  Legendre's  Geometry     ..........  2  50 

3.  Davies'  Analytical   Geometry  and  Calculus     .....  2  75 

4.  Davies'  Descriptive  Geometry    ..........  3  50 

MENSURATION. 

1.  Davies'  Practical  Mathematics  and  Mensuration    .    .    .  1  50 

2.  Davies'  Surveying   and   Navigation     ........  2  75 

3.  Davies'  Shades,  Shadows,  and   Perspective  .....  4  00 

MATHEMATICAL    SCIENCE. 

Davies'  Grammar  of  Arithmetic     ..........  *    50 

Davies'   Outlines  of  Mathematical  Science     ......  *1  00 

Davies'    Logic  and    Utility  of  Mathematics    ......  *1  50 

Davies  &.  Peck's  Dictionary  of  Mathematics      .....  *4  00 

10 


National  Series  of  Standard  School-Sooks. 

MATHEMATICS -continued. 

ARITHMETICAL    EXAMPLES. 

Reuck's  Examples  in  Denominate  Numbers  $   so 
Reuck's  Examples  in  Arithmetic l  00 

These  volumes  differ  from  the  ordinary  arithmetic  in  their  peculiarly 
practical  character.  They  are  composed  mainly  of  examples,  and  afford 
the  most  severe  and  thorough  discipline  for  the  mind.  While  a  book 
which  should  contain  a  complete  treatise  of  theory  and  practice  would  be 
too  cumbersome  for  every-day  use,  the  insufficiency  of  practical  examples 
has  been  a  source  of  complaint. 

HIGHER     MATHEMATICS. 

Church's  Elements  of  Calculus 2  50 

Church's  Analytical  Geometry 2  50 

Church's  Descriptive  Geometry,  with  Shades, 

Shadows,  and  Perspective 5  00 

These  volumes  constitute  the  "  West  Point  Course"  in  their  several 
departments. 

Courtenay's  Elements  of  Calculus    ....  3  75 

A  work  especially  popular  at  the  South. 

Hackley's  Trigonometry 3  75 

With  applications  to  navigation  and  surveying,  nautical  and  practical 
geometry  and  geodesy,  and  logarithmic,  trigonometrical,  and  nautical 
tables. 

THE     METRIC     SYSTEM. 

The  International  System  of  Uniform  Weights  and  Measures  must  hereafter  be 
taught  in  all  common-schools.  Professor  Charles  Davies  is  the  official  exponent  of 
the  system,  as  indicated  by  the  following  resolutions,  adopted  by  the  Committee  of  the 
House  of  Representatives,  on  a  "  Uniform  System  of  Coinage,  Weights,  and  Measures," 
February  2,  186T  :— 

Resolved,  That  this  committee  has  observed  with  gratification  the  efforts  made  by 
the  editors  and  publishers  of  several  mathematical  works,  designed  for  the  use  of  com- 
mon-schools and  other  institutions  of  learning,  to  introduce  the  Metric  System  of 
Weights  and  Measures,  as  authorized  by  Congress,  into  the  system  of  instruction  of 
the  youth  of  the  United  States,  in  its  various  departments ;  and,  in  order  to  extend 
further  the  knowledge  of  its  advantages,  alike  in  public  education  and  in  general  use 
by  the  people, 

Be  it  further  resolved,  That  Professor  Charles  Davies,  LL.D.,  of  the  State  of  New 
York,  be  requested  to  confer  with  superintendents  of  public  instruction,  and  teacher* 
of  schools,  and  others  interested  in  a  reform  of  the  present  incongruous  system,  and, 
by  lectures  and  addresses,  to  promote  its  general  introduction  and  use. 

The  official  version  of  the  Metric  System,  as  prepared  by  Dr.  Davies,  may  be  found 
in  the  Written,  Practical,  and  University  Arithmetics  ef  the  Mathematical  Series,  and 
U  also  published  separately,  price  postpaid,  fixe  cent*. 

12 


The  National  Series  of  Standard  School-Books. 


HISTORY. 


Monteith's  Youth's  History .    4    75 

A  History  of  the  United  States  for  beginners.  It  is  arranged  upon  the 
catechetical  plan,  with  illustrative  maps  and  engravings,  review  questions, 
dates  in  parentheses  (that  their  study  may  be  optional  with  the  younger 
class  of  learners),  and  interesting  Biographical  Sketches  of  all  persons 
who  have  been  prominently  identified  with  the  history  of  our  country. 

Willard's  United  States,  School  edition,  ...  i  50 

Do.  do.  University  edition,      .  2  50 

The  plan  of  this  standard  work  is  chronologically  exhibited  in  front  of 
the  title-page ;  the  Maps  and  Sketches  are  found  useful  assistants  to  the 
memory,  and  dates,  usually  so  difficult  to  remember,  are  so  systematically 
arranged  as  in  a  great  degree  to  obviate  the  difficulty.  Candor,  impar- 
tiality, and  accuracy,  are  the  distinguishing  features  of  the  narrative 
portion. 

Willard's  Universal  History, .  2  50 

The  most  valuable  features  of  the  "  United  States"  are  reproduced  in 
this.  The  peculiarities  of  the  work  are  its  great  conciseness  and  the 
prominence  given  to  the  chronological  order  of  events.  The  margin 
marks  each  successive  era  with  great  distinctness,  so  that  the  pupil  re- 
tains not  o:ily  the  event  but  its  time,  and  thus  fixes  the  order  of  history 
firmly  and  usefully  in  his  mind.  Mrs.  Willard's  books  are  constantly 
revised,  and  at  all  times  written  up  to  embrace  important  historical 
events  of  recent  date. 

Berard's  History  of  England, 1  60 

By  an  authoress  well  known  for  the  success  of  her  History  of  the  United 
States.  The  social  life  of  the  English  people  is  felicitously  interwoven, 
as  m  fact,  with  the  civil  and  military  transactions  of  the  realm. 

Ricord's  History  of  Rome, 1  50 

Possesses  the  charm  of  an  attractive  romance.     The  Fables  with  which 
this  history  abounds  are  introduced  in  such  a  way  as  not  to  deceive  the 
inexperienced,  while  adding  materially  to  the  value  of  the  work  as  a  reli- 
able index  to  the  character  and  institutions,  as  well  as  the  history  of  the 
»  Roman  people 

Hanna's  Bible  History, 1  60 

The  only  compendium  of  Bible  narrative  which  affords  a  connected  and 
chronological  view  of  the  important  events  there  recorded,  divested  of  all 
superfluous  detail. 

Alison's  History  of  Europe 2  so 

An  abridgment  for  Schools,  by  GOULD,  of  this  great  standard  work, 
covering  the  eventful  period  from  A.  D.  1789  to  18i5,  being  mainly  a  his- 
tory of  the  career  of  Napoleon. 

Marsh's  Ecclesiastical  History, 2  25 

Questions  to  ditto, 75 

Affording  the  History  of  the  Church  in  all  ages,  with  accounts  of  the 
pagan  world  during  Biblical  periods,  and  the  character,  rise,  and  progress 
of  sill  Religions,  as  well  as  the  various  socts  of  the  worshipers  of  Christ. 
The  work  is  entirely  non-sectarian,  though  strictly  catholic. 

13 


The  National  Series  of  Standard  School-ffoofci. 

P  E  N  M  AN  SHIP. 

Beers'  System  of  Progressive  Penmanship. 

Per  dozen  .............  $2  50 

This  "  round  hand  "  system  of  penmanship  in  twelve  numbers  com- 
mends itself  by  its  simplicity  and  thoroughness.  The  first  four  numbers 
are  primary  books.  Nos.  5  to  7,  advanced  books  for  boys.  Nos.  8  to  10 
advanced  books  for  girls.  Nos.  11  and  12,  ornamental  penmanship. 
These  books  are  printed  from  steel  plates  (engraved  by  McLees),  and  are 
unexcelled  in  mechanical  execution.  Large  quantities  are  annually  sold. 

Beers'  Slated  Copy  Slips,  per  set   .....    *50 

All  beginners  should  practice,  for  a  few  weeks,  slate  exercises,  familiar- 
izing them  with  the  form  of  the  letters,  the  motions  of  the  hand  and  arm, 
&c.,  &c.  These  copy  slips,  32  in  number,  supply  all  the  copies  found  C  i  a 
complete  series  of  writing-books,  at  a  trifling  cost 

Fulton  &  Eastman's  Copy  Books,  per  dozen  l  50 

A  series  for  the  economical,  —  complete  in  three  numbnrs.  (1)  Elemen- 
tary Exercises  :  (2)  Gentlemen's  Hand:  (3)  Ladies'  Hand. 

Fulton  &  Eastman's  Chirographic  Charts, 

2  Nos.,  per  set  ...........  *5  00 

To  embellish  the  school-room  walls,  and  furnish  class  exercise  in  the 
elements  of  Penmanship. 

DRAWING. 


Clark's  Elements  of  Drawing  ......    *75 

Containing  full  instructions,  with  appropriate  designs  and  copies  for  a 
complete  course  in  this  graceful  art,  from  the  first  rudiments  of  outline  to 
the  finished  sketches  of  landscape  and  scenery. 

Fowle's  Linear  and  Perspective  Drawing    *so 

For  the  cultivation  of  the  eye  and  hand,  with  copious  illustrations  and 
directions  which  will  enable  the  unskilled  teacher  to  learn  the  art  himself 
while  instructing  his  pupils. 

Beers'  Drawing-Cards,  per  set  ......    *25 

Embracing  a  large  variety  of  subjects  for  copies,  put  up  in  a  handsome 
package. 

The  Drawing-School,  per  set  .......  *l  50 

A  series  of  progressive  drawing-books,  presenting  copy  and  blank  upon 
the  same  page. 

Ripley's  Map  Drawing  .........  l  25 

One  of  the  most  efficient  aids  to  the  acquirement  of  a  knowledge  of 
geography  is  the  practice  of  map  drawing.  It  is  useful  for  the  same  rea- 
son that  th  '  best  exercise  in  orthography  is  the  writing  of  difficult  words. 
Sight  comes  to  the  aid  of  hearing,  and  a  double  impression  is  produced 
upon  the  memory.  Knowledge  becomes  less  mechanical  and  more  intui- 
tive. The  student  who  has  sketched  the  outlines  of  a  country,  and  dotted 
the  important  places,  is  little  likely  to  forget  either.  The  impression  pro- 
duced may  be  compared  to  that  of  a  traveler  who  has  been  over  the 
ground  —  while  more  comprehensive  and  accurate  in  detail. 


The  National  Series  of  Standard  School-Books. 

ELOCUTION. 

_ «— * 

Northend's  Little  Orator .   .   *60 

Contains  simple  and  attractive  pieces  in  prose  and  poetry,  adapted  to 
the  capacity  of  children  under  twelve  years  of  age. 

Northend's  National  Orator *i  25 

About  one  hundred  and  seventy  choice  pieces  happily  arranged.  The 
design  of  the  author  in  making  the  selection  has  been  to  cultivate  versa- 
tility of  expression. 

Northend's  Entertaining  Dialogues .   .    .    .*!  25 

Extracts  eminently  adapted  to  cultivate  the  dramatic  faculties,  as  well 
as  entertain  an  audience. 

Zachos'  Analytic  Elocution l  50 

All  departments  of  elocution— such  as  the  analysis  of  the  voice  and  the 
sentence,  phonology,  rhythm,  expression,  gesture,  &c. — are  here  arranged 
for  instruction  in  classes,  illustrated  by  copious  examples. 

Sherwood's  Self  Culture l  25 

Self  culture  in  reading,  speaking,  and  conversation— a  very  valuable 
treatise  to  those  who  would  perfect  themselves  in  these  accomplishments. 


BOOK-KEEPING. 


Smith  &  Martin's  Book-keeping l  oo 

Blanks  to  ditto *60 

This  work  is  by  a  practical  teacher  and  a  practical  book-keeper.  It  is 
of  a  thoroughly  popular  class,  and  will  be  welcomed  by  every  one  who 
loves  to  see  theory  and  practice  combined  in  an  easy,  concise,  and 
methodical  form. 

The  Single  Entry  portion  is  well  adapted  to  supply  a  want  felt  in  nearly 
all  other  treatises,  which  seem  to  be  prepared  mainly  for  the  use  of 
wholesale  merchants,  leaving  retailers,  mechanics,  farmers,  &c.,  who 
transact  the  greater  portion  of  the  business  of  the  country,  without  a 
guide.  The  work  is  also  commended  on  this  account  for  general  use  in 
Young  Ladies'  seminaries,  where  a  thorough  grounding  in  the  simpler  form 
of  accounts  will  be  invaluable  to  the  future  housekeepers  of  the  nation. 

The  treatise  on  Double  Entry  Book-keeping  combines  all  the  advan- 
tages of  the  most  recent  methods,  with  the  utmost  simplicity  of  applica- 
tion, thus  affording  the  pupil  all  the  advantages  of  actual  experience  in 
the  counting-house,  and  giving  a  clear  comprehension  of  the  entire  sub- 
ject through  a  judicious  course  of  mercantile  transactions. 

The  shape  of  the  book  is  such  that  the  transactions  can  be  presented  as 
in  actual  practice ;  and  the  simplified  form  of  Blanks,  three  in  number, 
adds  greatly  to  the  ease  experienced  in  acquiring  the  science. 

15 


The  National  Series  of  Standard  School- JBooks. 


NATURAL    SCIENCE. 


FAMILIAR    SCIENCE 
Norton  &  Porter's  First  Book  of  Scienco, '.  $1  so 

Bv  einioe'it  Professors  of  Yale  Collie.  Contains- the  principles  of 
Natural  Philosophy.  Astronomy,  Chemistry,  Physiology,  and  G  oloyy. 
Arranged  on  the  Catechetical  plan  for  primary  classes  and  beginners. 

Chambers'  Treasury  of  Knowledge,    ...  1  25 

Progressive  lessons  upon— /t/V,  common  things  which  lie  most  imme- 
diately around  us,  and  first  attract  the  attention  of  the  young  mind; 
se-oiui.  common  objects  from  the  Mineral,  Animal,  and  Vegetable  king- 
dom1:, ma  -mfactnred  articles,  and  miscellaneous  substances;  third,  a.  sys- 
tematic viiiv  of  Nature  under  the  various  sciences.  May  be  used  as  a 
Reader  or  Text-Book. 

NATURAL    PHILOSOPHY. 
Norton's  First  Book  in  Natural  Philosophy,  l  00 

By  Prof.  Xoitrox,  of  Yale  College.  Designed  for  beginners ;  profusely 
illustrated,  and  arranged  on  the  Catechetical  plan. 

Peck's  Ganot's  Course  of  Nat.  Philosophy,  l  88 

The  standard  text-book  of  France,  Americanized  and  popularized  by 
Prof.  PKCK,  of  Columbia  College.  The  most  magnificent  system  of  illus- 
tration ev.T  adopted  iu  an  American  school-book  is  here  found.  For 
intermediate  classes. 

Peck's  Elements  of  Mechanics, 2  50 

A  suitable  introduction  to  Bartlett's  higher  treatises  on  Mechanical 
Philosophy,  and  adequate  in  itself  for  a  complete  academical  course. 

Bartlett's  Synthetic  Mechanics, 4  oo 

Bartlett's  Analytical  Mechanics, 6  oo 

Bartlett's  Acoustics  and  Optics, 3  00 

A  system  of  Collegiate  Philosophy,  by  Prof.  BABTLETT,  of  West  Point 
Military  Academy. 

GEOLOGY. 
Page's  Elements  of  Geology, l  25 

A  volume  of  Chambers'  Educational  Course.  Practical,  simple,  and 
eminently  calculated  to  make  the  ftudy  interesting. 

Emmon's  Manual  of  Geology,    ......  l  50 

The  first  Geologist  of  the  country  has  here  produced  a  work  worthy  of 
his  reputation.    The  plan  of  presenting  the  subject  is  an  obvious  improve- 
ment on  older  methods.     The  department  of  Palaeontology  receives  espe- 
cial attention.  i  /» 
If 


The  National  Series  of  Standard  School-Books. 

NATURAL  SCIENCE-Continued. 

CHEMISTRY. 

Porter's  First  Book  of  Chemistry,    ...   .$1  oo 
Porter's  Principles  of  Chemistry,     .    .    .    .  2  oo 

The  above  are  widely  known  as  the  productions  of  one  of  the  most 
eminent  scientific  men  of  America.  The  extreme  simplicity  in  the  method 
of  presenting  the  science,  while  exhaustively  treated,  has  excited  uni- 
versal commendation.  Apparatus  adequate  to  the  performance  of  every 
experiment  mentioned,  may  be  had  of  the  publishers  for  a  trifling  Bum. 
The  effort  to  popularize  the  science  is  a  great  success.  It  is  now  within 
the  reach  of  the  poorest  and  least  capable  at  once. 

Darby's  Text-Book  of  Chemistry,    ....  1  75 

Purely  a  Chemistry,  divesting  the  subject  of  matters  comparatively 
foreign  to  it  (such  as  heat,  light,  electricity,  etc.),  but  usually  allowed  to 
engross  too  much  attention  in  ordinary  school-books. 

Gregory's  Organic  Chemistry, 3  oo 

Gregory's  Inorganic  Chemistry, 3  00 

The  science  exhaustively  treated.    For  colleges  and  medical  students. 


CHEMICAL    APPARATUS. 

To  accompany  Porter' 8  Chemistry. 

The  extreme  simplicity  of  the  science,  as  presented  in  this  book,  pats 
the  study,  in  point  of  expense,  within  the  reach  of  all.  A  complete  Ap- 
paratus (except  a  few  arti  'le«  which  can  be  obtained  of  any  druggist)  is 
pat  up  and  for  sale  by  the  publishers.  Price  $12.00. 

BOTANY. 
Thinker's  First  Lessons  in  Botany,  ....     eo 

For  children.  The  technical  terms  are  largely  dispensed  with  in  favor 
of  an  easy  and  familiar  style  adapted  to  the  smallest  learner. 

Wood's  Object  Lessons  in  Botany,  ....  1  53 

Wood's  Intermediate  Botany, 2  50 

Wood's  New  Class-Book  of  Botany,    ...  3  75 

The  standard  text-books  of  the  United  States  in  this  department  In 
Btvle  they  are  simple,  popular,  and  lively ;  in  arrangement,  easy  and  nat- 
ural ;  in  description,  graphic  and  strictly  exact.  The  Tables  for  Analysis 
ar  reduced  to  a  perfect  system.  More  are  annually  sold  than  of  all  others 
combined. 

Darby's  Southern  Botany, 2  °° 

Embracing  general  Structural  and  Physiological  Botany,  with  vegetable 
products,  and  descriptions  of  Southern  plants,  and  a  complete  Flora  of 
the  Southern  States.  ~ 


The  National  Series  of  Standard  School-'Boofcs* 

NATURAL  SCIENCE-Continued 

PHYSIOLOGY. 

Jarvis1  Primary  Physiology, $    so 

Jarvis'  Physiology  and  Laws  of  Health,    -  l  75 

The  only  books  extant  which  approach  this  subject  with  a  proper  view 
of  the  true  object  of  teaching  Physiology  in  schools,  viz.,  that  scholars 
may  know  how  to  take  care  of  their  own  health.  In  bold  contrast  with 
the  abstract  Anatomies,  which  children  learn  as  they  would  Greek  or 
Latin  (and  forget  as  soon),  to  discipline  the  mind,  are  these  text-book'', 
using  the  »nence  as  a  secondary  consideration,  and  only  so  far  as  is 
necessary  for  the  comprehension  of  the  laws  of  health. 

Hamilton's  Vegetable  &  Animal  Physiology,  1  25 

The  two  branches  of  the  science  combined  in  one  volume  lead  the  stu- 
dent to  a  proper  comprehension  of  the  Analogies  of  Nature. 

ASTRONOMY. 
Willard's  School  Astronomy, l  oo 

By  means  of  clear  and  attractive  illustrations,  addressing  the  eye  in 
many  cases  by  analogies,  careful  definitions  of  all  necessary  technical 
terms,  a  cai  ef  ul  avoidance  of  verbiage  and  unimportant  matter,  particular 
attention  to  analysis,  and  a  general  adoption  of  the  simplest  methods, 
Mrs.  Willard  has  made  the  best  and  most  attractive  elementary  Astron- 
omy e^aut. 

Mclntyre's  Astronomy  and  the  Globes,    .    .  l  so 

A  complete  treatise  for  intermediate  classes.     Highly  approved. 

Bartlett's  Spherical  Astronomy, 4  50 

The  West  Point  course,  for  advanced  classes,  with  applications  to  the 
current  wants  of  Navigation,  Geography,  and  Chronology. 

NATURAL  HISTORY. 
Carl's  Child's  Book  of  Natural  History,  .   .  o  50 

Illustrating  the  Animal,  Vegetable,  and  Mineral  Kingdoms,  with  appli- 
cation to  the  Arts.  For  beginners.  Beautifully  and  copiously  illustrated. 

ZOOLOGY. 
Chambers'  Elements  of  Zoology, l  so 

A  complete  and  comprehensive  system  of  Zoology,  adapted  for  aca- 
demic instruction,  presenting  a  systematic  view  of  the  Animal  Kingdom 
as  a  portion  of  external  Nature. 


$W  It  will  be  observed,  that,  in  the  various  departments  of  Natural  Science,  the 
NATIONAL  SEEIF.S  is  extremely  rich.  The  mineral,  animal,  and  vegetable  kingdoms, 
matter,  and  the  laws  that  govern  it  in  all  its  forms,  are  here  placed  before  the 
student  by  those  who  have  made  its  study  a  specialty  and  a  life  work.  The  works 
of  Professors  PKCK,  of  Columbia  College,  NOSTON  AND  POBTKE,  of  Yalo,  BAKJ- 
LETT,  of  West  Point  Military  Academy,  EMM  ENS,  of  Williams,  and  State  Geologist 
of  New  York  and  North  Carolina,  WOOD,  the  botanist,  and  JABVIS,  the  eminent  phy- 
sidiaivftre^fiafcgemed  indubitable  authority  in  all  that  concerns  their  several  specialties 

1  A 


National  Series  of  Standard  School-fiooks. 

MODERN  LANGUAGE. 


French  and  English  Primer, $   10 

German  and  English  Primer, 10 

Spanish  and  English  Primer, 10 

The  names  of  common  objects  properly  illustrated  and  arranged  in  easy 
lessons. 

Ledru's  French  Fables, 80 

Ledru's  French  Grammar, 1  oo 

Ledru's  French  Reader, 1  °o 

The  author's  long  experience  has  enabled  him  to  present  the  most  thor- 
oughly practical  text-books  extant,  in  this  branch.  The  system  of  pro- 
nunciation  (by  phonetic  illustration)  is  original  with  this  author,  and  will 
commend  itself  to  all  American  teachers,  as  it  enables  their  pupils  to  se- 
cure an  absolutely  correct  pronunciation  without  the  assistance  of  a  native 
master.  This  feature  is  peculiarly  valuable  also  to  "  self-taught"  students. 
The  directions  for  ascertaining  the  gender  of  French  nouns— also  a  great 
stumbling-block — are  peculiar  to  this  work,  and  will  bs  found  remarkably 
competent  to  the  end  proposed.  The  criticism  of  teachers  and  tho  tost  of 
the  school-room  is  invited  to  this  excellent  series,  with  confidence. 

Haskin's  French  and  English  First  Book    •     80 

Presents  the  striking  feature  of  a  simultaneous  presentation  of  the  ele- 
mentary principles  of  the  vernacular  with  those  of  a  foreign  language. 
This  is  the  method  which  the  practical  teacher  naturally  pursues  in  oral 
instruction,  and  possesses  peculiar  advantages  in  application  to  young 
pupils. 

Pujol's  Complete  French  Class-Book,  ...  2  50 

Offers,  in  one  volume,  methodically  arranged,  a  complete  French  course 
—usually  embraced  in  series  of  from  five  to  twelve  books,  including  the 
l)ulky  and  expensive  Lexicon.  Here  are  Gnimmar,  Conversation,  and 
c'.ioice  Literature — selected  from  the  best  French  autliors.  Each  branch 
is  thoroughly  bandied  ;  and  the  student,  havi;i'JT  diligently  completed  the 
course  as  prescribed,  may  consider  himself,  without  further  application, 
au  Suit  in  the  most  polite  and  elegant  languaga  of  modern  times. 

fflaurice-Poitevin's  Grammaire  Francaise,  •  1  oo 

American  schools  are  at  last  supplied  with  an  American  edition  of  this 
famous  text-book.  Many  of  our  best  institutions  have  for  years  been  pro- 
curing it  from  abroad  rather  than  forego  the  advantages  it  offers.  The 
policy  of  putting  students  who  have  acquired  some  proficiency  from  the 
ordinary  text-books,  into  a  Grammar  written  in  the  vernacular,  can  not 
be  too  highly  commended.  It  affords  an  opportunity  for  finish  and  review 
at  once ;  while  embodying  abundant  practice  of  its  own  rules. 

Worman's  Elementary  German  Grammar,  -  1  oo 

A  work  of  great  merit.  Well  calculated  to  ground  the  student  in  the 
elements  of  this  language,  become  BO  important  by  the  extensive  settle- 
ment of  Germans  in  this  country. 

Willard's  Historia  da  los  Estados  Unidos,  -  2  oo 

The  History  of  the  United  States,  translated  fov  Professors  TOI.OX  and 
Du  TouNoa,  will  be  found  a  valuable,  instructive,  aaU  uiloruiui.iar  read- 
ing-book for  Spanish  classes.  ^ 


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